Vaccinia viral A26 protein is a fusion suppressor of mature virus and triggers membrane fusion through conformational change at low pH.

Vaccinia mature virus requires A26 envelope protein to mediate acid-dependent endocytosis into HeLa cells in which we hypothesized that A26 protein functions as an acid-sensitive membrane fusion suppressor. Here, we provide evidence showing that N-terminal domain (aa1-75) of A26 protein is an acid-sensitive region that regulates membrane fusion. Crystal structure of A26 protein revealed that His48 and His53 are in close contact with Lys47, Arg57, His314 and Arg312, suggesting that at low pH these His-cation pairs could initiate conformational changes through protonation of His48 and His53 and subsequent electrostatic repulsion. All the A26 mutant mature viruses that interrupted His-cation pair interactions of His48 and His 53 indeed have lost virion infectivity. Isolation of revertant viruses revealed that second site mutations caused frame shifts and premature termination of A26 protein such that reverent viruses regained cell entry through plasma membrane fusion. Together, we conclude that viral A26 protein functions as an acid-sensitive fusion suppressor during vaccinia mature virus endocytosis.

Interleukin-37 is highly expressed in regulatory T cells of melanoma patients and enhanced by melanoma cell secretome.

Immune suppression is one of the 10 hallmarks of cancer. Interleukin-37 (IL-37), a member of the IL-1 family, inhibits both innate and adaptive immunity, and has been shown to modulate immune responses in various disease conditions. Yet, IL-37 has rarely been investigated in cancer patients, and its biological role in cancer remains to be elucidated. In this study, we investigated the gene expression of IL-37 in age- and sex-matched blood samples of healthy individuals and melanoma patients, and demonstrated upregulation of IL-37 messenger RNA (mRNA) in the blood samples of melanoma patients. By further analyzing immune cell subsets responsible for the upregulated IL-37 expression, we discovered that IL-37 mRNA was highly expressed in T cells and granulocytes, with the highest expression in regulatory T (Treg ) cells in healthy individuals, and that IL-37 mRNA was upregulated in lymphocytes (T, B, and natural killer cells) in melanoma patient blood. Among all cell subsets, Treg cells from melanoma patients exhibited the highest IL-37 gene expression levels. We provided evidence that melanoma-conditioned media induces IL-37 mRNA and protein expression in multiple lymphocyte populations, particularly in Treg cells. We further confirmed that the IL-1-mediated secretome from human melanoma cells, specifically transforming growth factor-ß, induces IL-37 mRNA expression in human Treg cells. Our results suggest a potential immunosuppressive role for IL-1 and IL-37 in melanoma tumorigenesis. Highly elevated IL-37 in specific lymphocyte populations could serve as a biomarker for tumor-induced immunosuppression.

CDK1 Interacts with Sox2 and Promotes Tumor Initiation in Human Melanoma.

: Cancers are composed of heterogeneous subpopulations with various tumor-initiating capacities, yet key stem cell genes associated with enhanced tumor-initiating capacities and their regulatory mechanisms remain elusive. Here, we analyzed patient-derived xenografts from melanoma, colon, and pancreatic cancer tissues and identified enrichment of tumor-initiating cells in MHC class I-hi cells, where CDK1, a master regulator of the cell cycle, was upregulated. Overexpression of CDK1, but not its kinase-dead variant, in melanoma cells increased their spheroid forming ability, tumorigenic potential, and tumor-initiating capacity; inhibition of CDK1 with pharmacologic agents reduced these characteristics, which was unexplained by the role of CDK1 in regulating the cell cycle. Proteomic analysis revealed an interaction between CDK1 and the pluripotent stem cell transcription factor Sox2. Blockade or knockdown of CDK1 resulted in reduced phosphorylation, nuclear localization, and transcriptional activity of Sox2. Knockout of Sox2 in CDK1-overexpressing cells reduced CDK1-driven tumor-initiating capacity substantially. Furthermore, GSEA analysis of CDK1hi tumor cells identified a pathway signature common in all three cancer types, including E2F, G2M, MYC, and spermatogenesis, confirming a stem-like nature of CDK1hi tumor cells. These findings reveal a previously unrecognized role for CDK1 in regulating tumor-initiating capacity in melanoma and suggest a novel treatment strategy in cancer via interruption of CDK1 function and its protein-protein interactions. SIGNIFICANCE: These findings uncover CDK1 as a new regulator of Sox2 during tumor initiation and implicate the CDK1-Sox2 interaction as a potential therapeutic target in cancer.

Downregulation of CITED2 contributes to TGFß-mediated senescence of tendon-derived stem cells.

Tendon-derived stem cells (TDSCs) are multipotent adult stem cells with potential applications in tendon and tendon-bone junction repair. However, cellular characteristics change during in vitro passaging. Therefore, elucidation of the molecular and cellular mechanisms of tendon aging will be essential for the development of TDSC-based therapies. The aim of this study is to investigate the effect of CITED2, a nuclear regulator and transforming growth factor ß2 (TGFß2) on TDSC proliferation and senescence by comparing cells derived from Achilles tendon biopsies of young individuals (Y-TDSC) with those of older patients (O-TDSC). Our results showed that CITED2 mRNA and protein expression levels were significantly higher in Y-TDSCs than in O-TDSCs and O-TDSCs displayed decreased proliferation and increased senescence compared with Y-TDSCs. Furthermore, high levels of CITED2 protein expression in Y-TDSCs correlated with the downregulation of SP1 and p21 and the upregulation of MYC, potentially indicating the mechanism by which CITED2 upregulates TDSC proliferation. TGFß2 was found to downregulate the expression of the CITED2 gene and knockdown of CITED2 abolished the effect of TGFß2 on TDSC proliferation and senescence. Thus, the downregulation of CITED2 contributes to TGFß-mediated senescence providing an insight into the molecular and cellular mechanisms that contribute to tendon aging and degeneration. Our findings may aid the development of cell-based therapies for tendon repair.

Use of a MCL-1 inhibitor alone to de-bulk melanoma and in combination to kill melanoma initiating cells.

MCL-1 (BCL-2 family anti-apoptotic protein) is responsible for melanoma's resistance to therapy. Cancer initiating cells also contribute to resistance and relapse from treatments. Here we examined the effects of the MCL-1 inhibitor SC-2001 in killing non melanoma-initiating-cells (bulk of melanoma), and melanoma-initiating-cells (MICs). By itself, SC-2001 significantly kills melanoma cells under monolayer conditions in vitro and in a conventional mouse xenograft model. However, even at high doses (10µM), SC-2001 does not effectively eliminate MICs. In contrast, the combination of SC-2001 with ABT-737 (a BCL-2/BCL-XL/BCL-W inhibitor) significantly decreases ALDH+ cells, disrupts primary spheres, and inhibits the self-renewability of MICs. These results were observed in multiple melanomas, including short term cultures of relapsed tumors from current treatments, independent of the mutation status of BRAF or NRAS. Using a low-cell-number mouse xenograft model, we examined the effects of these treatments on the tumor initiating ability of MIC-enriched cultures. The combination therapy reduces tumor formation significantly compared to either drug alone. Mechanistic studies using shRNA and the CRISPR-Cas9 technology demonstrated that the upregulation of pro-apoptotic proteins NOXA and BIM contribute to the combination-induced cell death. These results indicate that the MCL-1 inhibitor SC-2001 combined with ABT-737 is a promising treatment strategy for targeting melanoma.

Combining a GSI and BCL-2 inhibitor to overcome melanoma's resistance to current treatments.

Major limitations of current melanoma treatments are for instances of relapse and the lack of therapeutic options for BRAF wild-type patients who do not respond to immunotherapy. Many studies therefore focus on killing resistant subpopulations, such as Melanoma Initiating Cells (MICs) to prevent relapse. Here we examined whether combining a GSI (γ-Secretase Inhibitor) with ABT-737 (a small molecule BCL-2/BCL-XL/BCL-W inhibitor) can kill both the non-MICs (bulk of melanoma) and MICs. To address the limitations of melanoma therapies, we included multiple tumor samples of patients relapsed from current treatments, with a diverse genetic background (with or without the common BRAF, NRAS or NF1 mutations) in these studies. Excitingly, the combination treatment reduced cell viability and induced apoptosis of the non-MICs; disrupted primary spheres, decreased the ALDH+ cells, and inhibited the self-renewability of the MICs in multiple melanoma cell lines and relapsed patient samples. Using a low-cell-number mouse xenograft model, we demonstrated that the combination significantly reduced the tumor initiating ability of MIC-enriched cultures from relapsed patient samples. Mechanistic studies also indicate that cell death is NOXA-dependent. In summary, this combination may be a promising strategy to address treatment relapse and for triple wild-type patients who do not respond to immunotherapy.

Understanding melanoma stem cells.

Tumors are incredibly diverse and contain many different subpopulations of cells. The cancer stem cell (CSC) subpopulation is responsible for many aspects of tumorigenesis and has been shown to play an important role in melanoma development, progression, drug resistance and metastasis. However, it is becoming clear that tumor cell populations are dynamic and can be influenced by many factors, such as signals from the tumor microenvironment and somatic evolution. This review will present the current understanding of CSCs and the challenges of identifying and characterizing this dynamic cell population. The known characteristics and functions of melanoma stem cells, and the potential for therapeutic targeting of these cells in melanoma, will be discussed.

Efficacy of tripterygium glycosides tablet in treating ankylosing spondylitis: a systematic review and meta-analysis of randomized controlled trials.

Hundreds of randomized controlled trials (RCTs) on tripterygium glycosides tablet (TGT) in the treatment of ankylosing spondylitis (AS) have been published, but the therapeutic effects have never been systematically reviewed yet. The aim of this meta-analysis was to evaluate the efficacy of TGT on AS based on RCTs. PubMed, ScienceDirect, Cochrane Library, China Journals Full-text Database, and Wanfang Data were searched. The RCT quality was evaluated by the Cochrane Collaboration's tool for assessing risk of bias. The RCT characteristics including publication years, sample sizes, and follow-up periods as well as outcome measures including symptoms improvement, morning stiffness (MS), bath ankylosing spondylitis patient global score (BAS-G), pain index (PI), swelling index (SI), finger to floor distance (FFD), pillow wall distance (PWD), Schober test (Schober), erythrocyte sedimentation rate (ESR), and C reactive protein (CRP) were extracted. The odds ratio (OR), mean difference (MD), and its 95% confidence interval (CI) were selected for overall effect sizes. Subgroup, sensitivity, and meta-regression analyses were conducted to confirm the results. Eleven RCTs with 807 participants were included, the quality of which was moderate. OR of TGT in treating AS was 0.46 (95% CI 0.24, 0.90]. MD of MS was 11.79 (95% CI 3.13, 20.45). MD of BAS-G was 0.13 (95% CI -19.73, 19.99). MD of PI was 0.78 (95% CI 0.22, 1.34). MD of SI was 0.80 (95% CI 0.06, 1.53). MD of FFD was 0.80 (95% CI 0.06, 1.53). MD of PWD was 1.37 (95% CI -0.64, 3.38). MD of Schober was -0.36 (95% CI -0.65, -0.07]. MD of ESR was 4.58 (95% CI 2.10, 7.06). MD of CRP was 1.86 (95% CI -2.03, 5.76). Subgroup, sensitivity, and meta-regression analyses found the robust results. In conclusion, TGT could not treat AS effectively, as suggested by the moderate RCT quality and meta-analysis evidence.

Extracellular forms of IL-37 inhibit innate inflammation in vitro and in vivo but require the IL-1 family decoy receptor IL-1R8.

Similar to IL-1α and IL-33, IL-1 family member IL-37b translocates to the nucleus and is associated with suppression of innate and adaptive immunity. Here we demonstrate an extracellular function of the IL-37 precursor and a processed form. Recombinant IL-37 precursor reduced LPS-induced IL-6 by 50% (P < 0.001) in highly inflammatory human blood-derived M1 differentiated macrophages derived from selective subjects but not M2 macrophages. In contrast, a neutralizing monoclonal anti-IL-37 increased LPS-induced IL-6, TNFα and IL-1ß (P < 0.01). The suppression by IL-37 was consistently observed at low picomolar but not nanomolar concentrations. Whereas LPS induced a 12-fold increase in TNFα mRNA, IL-37 pretreatment decreased the expression to only 3-fold over background (P < 0.01). Mechanistically, LPS-induced p38 and pERK were reduced by IL-37. Recombinant IL-37 bound to the immobilized ligand binding α-chain of the IL-18 receptor as well as to the decoy receptor IL-1R8. In M1 macrophages, LPS increased the surface expression of IL-1R8. Compared with human blood monocytes, resting M1 cells express more surface IL-1R8 as well as total IL-1R8; there was a 16-fold increase in IL-1R8 mRNA levels when pretreated with IL-37. IL-37 reduced LPS-induced TNFα and IL-6 by 50-55% in mouse bone marrow-derived dendritic cells, but not in dendritic cells derived from IL-1R8-deficient mice. In mice subjected to systemic LPS-induced inflammation, pretreatment with IL-37 reduced circulating and organ cytokine levels. Thus, in addition to a nuclear function, IL-37 acts as an extracellular cytokine by binding to the IL-18 receptor but using the IL-1R8 for its anti-inflammatory properties.

Combining a BCL2 inhibitor with the retinoid derivative fenretinide targets melanoma cells including melanoma initiating cells.

Investigations from multiple laboratories support the existence of melanoma initiating cells (MICs) that potentially contribute to melanoma's drug resistance. ABT-737, a small molecule BCL-2/BCL-XL/BCL-W inhibitor, is promising in cancer treatments, but not very effective against melanoma, with the antiapoptotic protein MCL-1 as the main contributor to resistance. The synthetic retinoid fenretinide N-(4-hydroxyphenyl)retinamide (4-HPR) has shown promise for treating breast cancers. Here, we tested whether the combination of ABT-737 with 4-HPR is effective in killing both the bulk of melanoma cells and MICs. The combination synergistically decreased cell viability and caused cell death in multiple melanoma cells lines (carrying either BRAF or NRAS mutations) but not in normal melanocytes. The combination increased the NOXA expression and caspase-dependent MCL-1 degradation. Knocking down NOXA protected cells from combination-induced apoptosis, implicating the role of NOXA in the drug synergy. The combination treatment also disrupted primary spheres (a functional assay for MICs) and decreased the percentage of aldehyde dehydrogenase (high) cells (a marker of MICs) in melanoma cell lines. Moreover, the combination inhibited the self-renewal capacity of MICs, measured by secondary sphere-forming assays. In vivo, the combination inhibited tumor growth. Thus, this combination is a promising treatment strategy for melanoma, regardless of mutation status of BRAF or NRAS.

Suppression of antigen-specific adaptive immunity by IL-37 via induction of tolerogenic dendritic cells.

IL-1 family member IL-37 limits innate inflammation in models of colitis and LPS-induced shock, but a role in adaptive immunity remains unknown. Here, we studied mice expressing human IL-37b isoform (IL-37tg) subjected to skin contact hypersensitivity (CHS) to dinitrofluorobenzene. CHS challenge to the hapten was significantly decreased in IL-37tg mice compared with wild-type (WT) mice (-61%; P < 0.001 at 48 h). Skin dendritic cells (DCs) were present and migrated to lymph nodes after antigen uptake in IL-37tg mice. When hapten-sensitized DCs were adoptively transferred to WT mice, antigen challenge was greatly impaired in mice receiving DCs from IL-37tg mice compared with those receiving DCs from WT mice (-60%; P < 0.01 at 48 h). In DCs isolated from IL-37tg mice, LPS-induced increase of MHC II and costimulatory molecule CD40 was reduced by 51 and 31%, respectively. In these DCs, release of IL-1ß, IL-6, and IL-12 was reduced whereas IL-10 secretion increased (37%). Consistent with these findings, DCs from IL-37tg mice exhibited a lower ability to stimulate syngeneic and allogeneic naive T cells as well as antigen-specific T cells and displayed enhanced induction of T regulatory (Treg) cells (86%; P < 0.001) in vitro. Histological analysis of CHS skin in mice receiving hapten-sensitized DCs from IL-37tg mice revealed a marked reduction in CD8(+) T cells (-74%) but an increase in Treg cells (2.6-fold). Together, these findings reveal that DCs expressing IL-37 are tolerogenic, thereby impairing activation of effector T-cell responses and inducing Treg cells. IL-37 thus emerges as an inhibitor of adaptive immunity.

Crystallization and X-ray diffraction of virus-like particles from a piscine betanodavirus.

Dragon grouper nervous necrosis virus (DGNNV), a member of the genus Betanodavirus, causes high mortality of larvae and juveniles of the grouper fish Epinephelus lanceolatus. Currently, there is no reported crystal structure of a fish nodavirus. The DGNNV virion capsid is derived from a single open reading frame that encodes a 338-amino-acid protein of approximately 37 kDa. The capsid protein of DGNNV was expressed to form virus-like particles (VLPs) in Escherichia coli. The VLP shape is T = 3 quasi-symmetric with a diameter of ∼38 nm in cryo-electron microscopy images and is highly similar to the native virion. In this report, crystals of DGNNV VLPs were grown to a size of 0.27 mm within two weeks by the hanging-drop vapour-diffusion method at 283 K and diffracted X-rays to ∼7.5 Šresolution. In-house X-ray diffraction data of the DGNNV VLP crystals showed that the crystals belonged to space group R32, with unit-cell parameters a = b = 353.00, c = 800.40 Å, α = ß = 90, γ = 120°. 23 268 unique reflections were acquired with an overall Rmerge of 18.2% and a completeness of 93.2%. Self-rotation function maps confirmed the fivefold, threefold and twofold symmetries of the icosahedron of DGNNV VLPs.

MiR397b regulates both lignin content and seed number in Arabidopsis via modulating a laccase involved in lignin biosynthesis.

Plant laccase (LAC) enzymes belong to the blue copper oxidase family and polymerize monolignols into lignin. Recent studies have established the involvement of microRNAs in this process; however, physiological functions and regulation of plant laccases remain poorly understood. Here, we show that a laccase gene, LAC4, regulated by a microRNA, miR397b, controls both lignin biosynthesis and seed yield in Arabidopsis. In transgenic plants, overexpression of miR397b (OXmiR397b) reduced lignin deposition. The secondary wall thickness of vessels and the fibres was reduced in the OXmiR397b line, and both syringyl and guaiacyl subunits are decreased, leading to weakening of vascular tissues. In contrast, overexpression of miR397b-resistant laccase mRNA results in an opposite phenotype. Plants overexpressing miR397b develop more than two inflorescence shoots and have an increased silique number and silique length, resulting in higher seed numbers. In addition, enlarged seeds and more seeds are formed in these miR397b overexpression plants. The study suggests that miR397-mediated development via regulating laccase genes might be a common mechanism in flowering plants and that the modulation of laccase by miR397 may be potential for engineering plant biomass production with less lignin.

Targeting glucose metabolism in chondrosarcoma cells enhances the sensitivity to doxorubicin through the inhibition of lactate dehydrogenase-A.

Chondrosarcoma is a malignant cartilage-forming cancer composed of cells derived from transformed cells that produce cartilage. Conventional chemotherapy and radiotherapy have very limited efficacy in patients with advanced chondrosarcoma. In the present study, we reported a novel therapeutic approach in the treatment of chondrosarcoma cells. We detected that lactate dehydrogenase-A (LDHA) is highly active in chondrosarcoma cells and chondrosarcoma patient samples compared with normal chondrocyte cell lines and primary human chondrocyte. Moreover, chondrosarcoma cells exhibited elevated levels of LDHA expression under doxorubicin treatment. To further explore the mechanisms, we generated doxorubicin-resistant cells from SW1353 chondrosarcoma cell line. Notably, the activity and expression of LDHA are upregulated in doxorubicin-resistant cells. Moreover, our data showed a strong correlation between glucose metabolism and doxorubicin resistance in chondrosarcoma cells; doxorubicin-resistant cells displayed highly activated glucose metabolism and depended more on glucose supply. Finally, we reported a synergistic effect produced by incorporating doxorubicin with glycolysis inhibitors-oxamate in the combined treatment of chondrosarcoma cells in vitro and in vivo. In summary, the present study may aid in the development of new approaches using the combination of chemotherapeutic agents for the treatment of chondrosarcoma patients.

[Clinical study on treatment of posterolateral fracture of tibial plateau via superior fibular head approach].

OBJECTIVE: To observe the effectiveness of the superior fibular head approach for the treatment of posterolateral fracture of the tibial plateau. METHODS: Between June 2010 and February 2012, 20 cases of posterolateral fracture of the tibial plateau were treated through superior fibular head approach, including 1 case of simple posterolateral fracture of the tibial plateau and 19 cases of posterolateral fracture of the tibial plateau with other fractures. There were 12 males and 8 females with an average age of 42.2 years (range, 28-58 years). All patients had closed fractures. Fracture was caused by traffic accident in 14 cases, by falling from height in 4 cases, and by twist injury in 2 cases. Associated injuries included lateral meniscus injury in 5 cases, medial meniscus injury in 2 cases, and anterior cruciate ligament injury in 1 case. The time from injury to admission ranged from 90 minutes to 32 hours (mean, 4.5 hours), and the time from admission to operation was 5-12 days (mean, 7.8 days). All cases underwent fracture reduction and fixation with Pilon plates through the superior fibular head approach, and associated fracture and meniscal injury were treated. RESULTS: All incisions healed by first intention, and no numbness or articular instability occurred. All patients were followed up 6-26 months (mean, 19.1 months). The average fracture healing time was 10.2 weeks (range, 8-12 weeks). During following-up, no related complication of fixation loosening or articular surface loss occurred. According to Rasmussen knee score criteria at last follow-up, the score was 18-30 (mean, 27.9); 16 cases were graded as excellent, 3 cases as good, and 1 case as fair, with an excellent and good rate of 95%. CONCLUSION: The superior fibular head approach for the treatment of posterolateral fracture of the tibial plateau is simple, safe, and effective, and can achieve a good surgical outcome.

Dual role of apoptosis-associated speck-like protein containing a CARD (ASC) in tumorigenesis of human melanoma.

Apoptosis-associated Speck-like protein containing a CARD (caspase recruitment domain) (ASC) was originally named because it triggered apoptosis in certain tumors. More recently, however, ASC was found to be a central adaptor protein of inflammasome, which mediates the secretion of protumorigenic inflammation. Here we examined the role of ASC in tumorigenesis of human melanoma. Compared with primary melanoma, ASC protein expression was generally downregulated in metastatic melanoma. Although overexpressing ASC in metastatic melanoma showed no effects on cell viability, silencing ASC with short hairpin RNA induced G1 cell cycle arrest, reduced cell viability, and suppressed tumorigenesis in metastatic melanoma. On the other hand, silencing ASC in primary melanoma reduced cell death, increased cell viability, and enhanced tumorigenesis. In primary and metastatic melanoma cells, ASC knockdown inhibited inflammasome-mediated caspase-1 activity and IL-1ß secretion. However, phosphorylated IκB kinase (IKK)α/ß expression and NF-κB activity were suppressed in metastatic melanoma and enhanced in primary melanoma after ASC knockdown. These findings suggest stage-dependent dual roles of ASC in tumorigenesis. ASC expression in primary melanoma inhibits tumorigenesis by reducing IKKα/ß phosphorylation and inhibiting NF-κB activity. In metastatic melanoma, on the other hand, this inhibitory effect is diminished, and ASC induces tumorigenic pathways through enhanced NF-κB activity and inflammasome-mediated IL-1ß secretion.

Isolation of human melanoma stem cells using ALDH as a marker.

This unit describes a protocol for establishing a patient-derived tumor xenograft model (PDTX model) of human melanoma and isolating human melanoma stem cells from human melanoma specimens using aldehyde dehydrogenase (ALDH) as a marker. One major limitation of analyzing a small fraction of cancer stem cells from patient tumor samples is that substantial quantities of fresh tumor tissues are not available. To overcome this challenge, we have established a PDTX model of human melanoma. In this model, human tumor tissues obtained from melanoma patients are dissected into small pieces and subsequently implanted into immunocompromised mice. The PDTX tumors retain fundamental genotypic and phenotypic features of the original tumors and are suitable for further biological analyses. Using the PDTX model, we have analyzed ALDH-labeled human melanoma stem cells. This unit will describe how to establish a PDTX model using human tumor samples. We will also describe how to isolate and analyze ALDH-labeled human melanoma stem cells using this model.

ABT-737 synergizes with Bortezomib to kill melanoma cells.

The BH3 mimetic ABT-737 is a potent inhibitor of the anti-apoptotic proteins Bcl-2, Bcl-X(L), and Bcl-w. The Bcl-2 family modulates sensitivity to anticancer drugs in many cancers, including melanomas. In this study, we examined whether ABT-737 is effective in killing melanoma cells either alone or in combination with a proteasome inhibitor already in clinical use (Bortezomib) in vitro and in vivo, and further evaluated the mechanisms of action. Results showed that ABT-737 alone induced modest cytotoxicity in melanoma cells, but only at higher doses. Knock-down of the anti-apoptotic proteins Bcl-2, Bcl-X(L), or Mcl-1 with siRNAs demonstrated that Mcl-1 is the critical mediator of melanoma's resistance to ABT-737 treatment. However, ABT-737 displayed strong synergistic lethality when combined with Bortezomib. Immunoblot analyses demonstrated that Bortezomib increased expression of Noxa, a pro-apoptotic Bcl-2 member that antagonizes Mcl-1. Additionally, siRNA-mediated inhibition of Noxa expression protected melanoma cells from cytotoxicity induced by the combination treatment. These results demonstrate that Bortezomib synergizes with ABT-737 by neutralizing Mcl-1's function via increased levels of Noxa. In a xenograft mouse model, although drug doses were limited due to toxicity, ABT-737 or Bortezomib slowed melanoma tumor growth compared to the control, and the drug combination significantly decreased growth compared to either drug alone. These data imply that less toxic drugs fulfilling a function similar to Bortezomib to neutralize Mcl-1 are promising candidates for combination with ABT-737 for treating melanomas.

[Effectiveness comparison of operative and non-operative treatment for complex proximal humeral fractures in elderly patients].

OBJECTIVE: To compare the effectiveness between operative and non-operative treatment for 3- and 4-part proximal humeral fractures in elderly patients. METHODS: Between January 2009 and January 2011, 35 patients with 3- or 4-part proximal humeral fractures were treated with open reduction and locking plate internal fixation (n = 20, operative group) and with closed reduction and splint or cast fixation (n = 15, non-operative group). There was no significant difference in gender, age, etiology, fracture type, and disease duration between 2 groups (P > 0.05). The postoperative rehabilitation protocol was performed in 2 groups. RESULTS: All patients of the operative group achieved healing of incision by first intention. All patients were followed up 16 months on average (range, 12-20 months). The X-ray films showed that the other fractures healed except 1 case (5.0%) nonunion in operative group. Varus malunion was found in 1 case (6.7%) of non-operative group and 2 cases (10.0%) of operative group. Humeral head necrosis was found in 1 case respectively in 2 groups (5.0% and 6.7%). There was no significant difference in complication incidence between 2 groups (P > 0.05). The Constant-Murley scores of non-operative group and operative group were 64.7 +/- 9.9 and 66.8 +/- 11.8 at last follow-up respectively, showing no significant difference (t = 0.59, P = 0.47). CONCLUSION: Operative treatment has similar effectiveness to non-operative treatment for 3- and 4-part proximal humeral fractures. In elderly patients, non-operative treatment should be chosen.