Sequential administration of delta-tocotrienol ameliorates radiation-induced myelosuppression in mice and non-human primates through inducing G-CSF production

To date only four recombinant growth factors, including Filgrastim (rhG-CSF), have been approved by FDA as radiomitigators to ameliorate hematopoietic acute radiation syndrome (H-ARS). These approved agents are not stable under room-temperature, needing to be stored at 2-8 °C, and would not be feasible in a mass casualty scenario where rapid and cost-effective intervention is crucial. Delta-tocotrienol (δ-T3H), the most potent G-CSF-inducing agent among vitamin E isoforms, exhibited efficiency and selectivity on G-CSF production in comparison with TLR and STING agonists in mice. Five-dose δ-T3H was utilized as the optimal therapeutic regimen due to long-term G-CSF production and the best peripheral blood (PB) recovery of irradiated mice. Comparable with rhG-CSF, sequential administration of δ-T3H post-irradiation improved hematologic recovery and accelerated the regeneration of hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) in the bone marrow (BM) and spleen of 6.5Gy irradiated mice; and consistently enhanced repopulation of BM-HSCs. In 4.0Gy irradiated nonhuman primates, δ-T3H exhibited comparable efficacy as rhG-CSF to promote PB recovery and colony-formation of BM-HPCs. Altogether, we demonstrated that sequential administration of delta-tocotrienol ameliorates radiation-induced myelosuppression in mice and non-human primates through inducing G-CSF production, indicated δ-T3H as a promising radiomitigator for the management of H-ARS, particularly in a mass casualty scenario.

Radioprotective effectiveness of a novel delta-tocotrienol prodrug on mouse hematopoietic system against 60Co gamma-ray irradiation through inducing granulocyte-colony stimulating factor production

Considering the increasing risk of nuclear attacks worldwide, the development of develop potent and safe radioprotective agents for nuclear emergencies is urgently needed. γ-tocotrienol (GT3) and δ-tocotrienol (DT3) have demonstrated a potent radioprotective effect by inducing the production of granulocyte-colony stimulating factor (G-CSF) in vivo. However, their application is limited because of their low bioavailability. The utilization of ester prodrugs can be an effective strategy for modifying the pharmacokinetic properties of drug molecules. In this study, we initially confirmed that DT3 exhibited the most significant potential for inducing G-CSF effects among eight natural vitamin E homologs. Consequently, we designed and synthesized a series of DT3 ester and ether derivatives, leading to improved radioprotective effects. The metabolic study conducted in vitro and in vivo has identified DT3 succinate 5b as a prodrug of DT3 with an approximately seven-fold higher bioavailability compared to DT3 alone. And DT3 ether derivative 8a were relatively stable and approximately 4 times more bioavailable than DT3 prototype. Furthermore, 5b exhibited superior ability to mitigate radiation-induced pancytopenia, enhance the recovery of bone marrow hematopoietic stem and progenitor cells, and promote splenic extramedullary hematopoiesis in sublethal irradiated mice. Similarly, 8a shown potential radiation protection, but its radiation protection is less than DT3. Based on these findings, we identified 5b as a DT3 prodrug, and providing an attractive candidate for further drug development.

Fluacrypyrim Protects Hematopoietic Stem and Progenitor Cells against Irradiation via Apoptosis Prevention

Ionizing radiation (IR)-induced hematopoietic injury has become a global concern in the past decade. The underlying cause of this condition is a compromised hematopoietic reserve, and this kind of hematopoietic injury could result in infection or bleeding, in addition to lethal mishaps. Therefore, developing an effective treatment for this condition is imperative. Fluacrypyrim (FAPM) is a recognized effective inhibitor of STAT3, which exhibits anti-inflammation and anti-tumor effects in hematopoietic disorders. In this context, the present study aimed to determine whether FAPM could serve as a curative agent in hematopoietic-acute radiation syndrome (H-ARS) after total body irradiation (TBI). The results revealed that the peritoneally injection of FAPM could effectively promote mice survival after lethal dose irradiation. In addition, promising recovery of peripheral blood, bone marrow (BM) cell counts, hematopoietic stem cell (HSC) cellularity, BM colony-forming ability, and HSC reconstituting ability upon FAPM treatment after sublethal dose irradiation was noted. Furthermore, FAPM could reduce IR-induced apoptosis in hematopoietic stem and progenitor cells (HSPCs) both in vitro and in vivo. Specifically, FAPM could downregulate the expressions of p53-PUMA pathway target genes, such as Puma, Bax, and Noxa. These results suggested that FAPM played a protective role in IR-induced hematopoietic damage and that the possible underlying mechanism was the modulation of apoptotic activities in HSCs.

POS0535 OUTCOMES IN PATIENTS WITH RHEUMATOID ARTHRITIS INITIATING THERAPY WITH ETANERCEPT, ADALIMUMAB, OR JANUS KINASE INHIBITORS

Background

Ongoing debate exists regarding the optimal sequence of tumor necrosis factor inhibitors and Janus kinase inhibitors (JAKis) in patients with rheumatoid arthritis (RA) as first-line biologic or targeted synthetic disease-modifying antirheumatic drug (b/tsDMARD) therapy following conventional therapies.

Objectives

To describe baseline characteristics, effectiveness, persistency, and treatment patterns among first-line b/tsDMARD-naive initiators of etanercept (ETN), adalimumab (ADA), or JAKis (tofacitinib, baricitinib, and upadacitinib).

Methods

Data on patients who initiated b/tsDMARD from 11/2012 to 6/2021 were obtained from the CorEvitas RA Registry, a prospective, multicenter, observational, disease-based registry. Patients ≥18 years with rheumatologist-diagnosed RA and 6- and/or 12-months’ (M) follow-up were included. We report descriptive statistics at baseline, persistency on therapy, escalation/de-escalation of therapy, details on patterns of drug switching, and effectiveness outcomes using regression models adjusted for baseline covariates (demographic/socioeconomic/lifestyle characteristics, comorbidities, medication history, disease activity, and patient-reported outcomes). Outcomes were evaluated at 6M and 12M follow-up.

Results

First-line initiators of ETN, ADA, and JAKis with baseline and follow-up visits were identified: 803, 984, and 361 patients at 6M, respectively; 589, 749, and 264 patients at 12M, respectively. Baseline characteristics were similar among ETN, ADA, and JAKi initiators with the exception of disease duration, which was longer among first-line JAKi initiators (mean, 8.6 y) versus ETN (5.9 y) and ADA (5.8 y) initiators. Unadjusted mean improvement in Clinical Disease Activity Index (CDAI) was generally similar between groups at 6M and 12M (Table 1). Adjusted effectiveness results were similar at 6M and 12M (Figure 1). At 6M, 68% of ETN, 69% of ADA, and 67% of JAKi initiators remained on the same therapy; at 12M, 53% of ETN, 57% of ADA, and 57% of JAKi initiators remained on the same therapy. The frequency of switching to another b/tsDMARD was similar across initiators.

Table 1.

Patient Description at Time of Initiation and Unadjusted Disease Activity Results

ETNADAJAKisAge, years54.4 (12.8)55.5 (12.1)60.9 (12.5)Female, n (%)666 (77)843 (76)303 (77)BMI, kg/m230.4 (7.6)31.3 (7.9)30.8 (7.6)Duration of RA, years5.9 (7.6)5.8 (7.3)8.6 (10.0)BL disease activitya CDAI19.9 (14.3)18.9 (12.7)18.8 (13.2) mHAQ0.5 (0.5)0.5 (0.5)0.5 (0.5) Patient painb48.0 (28.8)49.2 (28.5)45.2 (29.2)Disease activity decrease from BL at 6M CDAI6.9 (13.6)6.4 (12.1)4.7 (12.3) mHAQ0.1 (0.4)0.1 (0.4)0.1 (0.4) Patient painb9.7 (30.2)10.6 (28.4)8.9 (29.5)Disease activity decrease from BL at 12M CDAI7.4 (13.5)6.1 (13.0)5.1 (13.0) mHAQ0.1 (0.4)0.1 (0.4)0.1 (0.4) Patient painb8.8 (29.7)8.7 (30.1)7.5 (28.6)Achievement of LDAc, % 6M43.441.932.5 12M41.039.638.3

aBaseline for combined population with 6M and 12M follow-up. b(range: 0–100). cCDAI ≤10 among those with moderate or high disease activity at baseline.

Data are mean (SD) unless otherwise specified.

ADA, adalimumab; BL, baseline; CDAI, Clinical Disease Activity Index; ETN, etanercept; JAKis, Janus kinase inhibitors; LDA, low disease activity; M, months; mHAQ, modified Health Assessment Questionnaire; RA, rheumatoid arthritis; SD, standard deviation.

Conclusion

In this real-world study in patients initiating first-line b/tsDMARD therapy with ETN, ADA, or JAKis, we did not observe differences in clinical effectiveness/patient-reported outcomes and treatment persistency at 6M and12M after treatment initiation.

Acknowledgements

This study is sponsored by CorEvitas, LLC. CorEvitas has been supported through contracted subscriptions in the last two years by AbbVie, Amgen Inc., Arena, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, Chugai, Eli Lilly and Company, Genentech, Gilead, GSK, Janssen, LEO, Novartis, Ortho Dermatologics, Pfizer Inc., Regeneron, Sanofi, Sun, and UCB. Writing support was funded by Amgen Inc. and provided by Su Cappello, PharmD, of Peloton Advantage, LLC, an OPEN Health company, and Julie Wang, DPM, of Amgen Inc.

Disclosure of Interests

Dimitrios A Pappas Shareholder of: Officer or Board Member for Corrona Research Foundation, Speakers bureau: Speaker/Honoraria for AbbVie, Novartis, Roche Hellas, Sanofi, Consultant of: Consultant for AbbVie, Roche Hellas; Advisor for Sanofi, Employee of: Employment by, ownership interest, and stock options in CorEvitas, LLC, Jacqueline O’Brien Employee of: Employment by CorEvitas, LLC., Lin Guo Employee of: Employment by CorEvitas, LLC., Ying Shan Employee of: Employment by CorEvitas, LLC., Joshua Baker Consultant of: Received consulting fees from Bristol Myers Squibb, Pfizer, CorEvitas LLC, and Burns-White, LLC., Greg Kricorian Shareholder of: Employment by and stock ownership in Amgen Inc., Employee of: Employment by and stock ownership in Amgen Inc., Scott Stryker Shareholder of: Employment by and stock ownership in Amgen Inc., Employee of: Employment by and stock ownership in Amgen Inc., David Collier Shareholder of: Employment by and stock ownership in Amgen Inc., Employee of: Employment by and stock ownership in Amgen Inc.

[Analysis of clinical phenotype and genotype of Chinese children with disorders of sex development]

Objective: To explore the heterogeneity and correlation of clinical phenotypes and genotypes in children with disorders of sex development (DSD). Methods: A retrospective study of 1 235 patients with clinically proposed DSD in 36 pediatric medical institutions across the country from January 2017 to May 2021. After capturing 277 DSD-related candidate genes, second-generation sequencing was performed to analyzed the heterogeneity and correlation combined with clinical phenotypes. Results: Among 1 235 children with clinically proposed DSD, 980 were males and 255 were females of social gender at the time of initial diagnosis with the age ranged from 1 day of age to 17.92 years. A total of 443 children with pathogenic variants were detected through molecular genetic studies, with a positive detection rate of 35.9%. The most common clinical phenotypes were micropenis (455 cases), hypospadias (321 cases), and cryptorchidism (172 cases) and common mutations detected were in SRD5A2 gene (80 cases), AR gene (53 cases) and CYP21A2 gene (44 cases). Among them, the SRD5A2 mutation is the most common in children with simple micropenis and simple hypospadias, while the AMH mutation is the most common in children with simple cryptorchidism. Conclusions: The SRD5A2 mutation is the most common genetic variant in Chinese children with DSD, and micropenis, cryptorchidism, and hypospadias are the most common clinical phenotypes. Molecular diagnosis can provide clues about the biological basis of DSD, and can also guide clinicians to perform specific clinical examinations. Target sequence capture probes and next-generation sequencing technology can provide effective and economical genetic diagnosis for children with DSD.

Photoluminescence and magnetism integrated multifunctional black phosphorus probes through controllable PO bond orbital hybridization

Biological probes with integrated photoluminescence and magnetism characteristics play a critical role in modern clinical diagnosis and surgical protocols combining fluorescence optical imaging (FOI) with magnetic resonance imaging (MRI) technology. However, traditional magnetic semiconductors can easily generate a spin splitting at the Fermi level and half-metallic electronic occupation, which will sharply reduce the radiation recombination efficiency of photogenerated carriers. To overcome this intrinsic contradiction, we propose a controllable oxidation strategy to introduce some particular PO bonds into black phosphorus nanosheets, in which the p orbital hybridization between P and O atoms not only provides some carrier recombination centers but also leads to a room-temperature spin polarization. As a result, the coexistence of photoluminescence and magnetism is realized in multifunctional black phosphorus probes with excellent biocompatibility. This work provides a new insight into integrating photoluminescence and magnetism together by intriguing atomic orbital hybridization.

Salvage mandibular reconstruction: multi-institutional analysis of 17 patients

Unsuccessful mandibular reconstruction occasionally occurs, leaving the patient with undesirable function and contours. In such cases, second- or third-time corrective operations are challenging. However, published studies on the complicated retreatment of such patients are scarce. A retrospective analysis covering the years 2015-2019 was conducted in three centers. All 17 patients included had undergone prior failed mandibular reconstructions in other institutions. Salvage secondary or tertiary reconstructive surgeries were attempted and the results are presented. Major factors for these failed reconstructions included exposed non-vascularized bone grafts (n = 7, 41.2%), flap loss (n = 4, 23.5%), exposed artificial joint (n = 3, 17.6%), skewed occlusion with deformity (n = 1, 5.9%), non-union (n = 1, 5.9%), and recurrence (n = 1, 5.9%). Fibula flaps were transferred in 15 patients, while iliac flaps were used in two patients for mandibular re-do reconstructions. Virtual surgical designs were conducted in nine (52.9%) patients, with navigation-guided approaches performed in three cases. Postoperative functions were relatively favorable in these complicated mandibular re-do reconstruction cases. Mandibular symmetry (mandibular length and height; P = 0.002) and condylar position (P < 0.001) were regained after these re-do attempts. Secondary or tertiary mandibular re-do reconstruction can still achieve good functional outcomes with appropriate preoperative selection and well-conceived designs, especially with the aid of virtual surgery and navigation.

AB0202 IMPROVEMENT IN CLINICAL DISEASE ACTIVITY AND PATIENT-REPORTED OUTCOMES AFTER 6 MONTHS OF TREATMENT WITH ABATACEPT, STRATIFIED BY LINE OF THERAPY, IN PATIENTS WITH RA: RESULTS FROM A LARGE, US, NATIONAL OBSERVATIONAL STUDY

Background:

RA is more responsive to treatment in the early stages of disease, and early treatment may lead to better long-term outcomes.1,2 Data on the effectiveness of specific drugs as first or later lines of therapy will help inform treatment sequencing.

Objectives:

Data from patients enrolled in the Corrona RA Registry were used to compare the effectiveness of abatacept across lines of therapy overall (primary cohort) and in a subset of patients who were anti-citrullinated protein antibody positive (ACPA+).

Methods:

Patients with RA who initiated abatacept (January 2006 to October 2020), had 6 months’ follow-up (within 4−9 months of starting abatacept), had baseline (BL) and follow-up CDAI scores available, and had BL CDAI >2.8 were included. Outcomes were compared for first-, second- and third or higher-line therapy: 0, 1 or ≥2 prior biologic DMARDs or Janus kinase inhibitors, respectively. Continuous outcomes included change from BL to 6 months in mean CDAI and patient-reported pain, fatigue, and HAQ. Binary outcomes included rate of achieving minimal clinically important difference (MCID) in CDAI or modified ACR20/50/70 at 6 months. Continuous and binary outcomes were analysed using multiple linear and logistic regression, respectively. The models included line of therapy, age, sex, disease duration, work status, SC nodules, history of hypertension and depression, BL CDAI, BL patient-reported pain and BL fatigue. Additional subgroup analyses were carried out in patients with moderate/high disease activity (CDAI >10) at BL.

Results:

In total, 2876 patients (2327 with BL CDAI >10; 890 ACPA+) were included; 442, 911, and 1523 patients initiated first-, second- or third/higher-line abatacept, respectively. Compared with patients on second/third/higher-line abatacept therapy, those on first-line abatacept were significantly older, had shorter disease duration, and had lower BL CDAI, pain and fatigue (all p<0.001). In adjusted analyses, patients receiving abatacept as earlier lines of therapy had significantly greater improvement from BL in mean CDAI and in patient-reported fatigue and HAQ (Table 1). There was no significant difference between lines of therapy in change in patient-reported pain. Patients receiving first-line abatacept had significantly higher odds of achieving a MCID in CDAI or modified ACR20/50/70 response (Figure 1). Similar patterns were seen when the sample was limited to patients with moderate/high disease activity or in patients who were ACPA+.

Conclusion:

There were significant differences in improvement in clinical disease activity and patient-reported outcomes across lines of therapy. Better treatment responses were observed with earlier lines of abatacept therapy in the overall population, in patients who were ACPA+ and in those with moderate/high BL disease activity.

References:

[1]Harrold LR, et al. Clin Rheumatol 2017;36:1215−1220.

[2]Monti S, et al. RMD Open 2015;1(Suppl 1):e000057.

Table 1.

Adjusted mean change in CDAI and patient-reported outcomes from BL to 6 months after initiation of abatacept by line of therapy (primary cohort)

Adjusted outcome, mean change (SE)First-line (n=440)Second-line (n=898)Third/higher-line (n=1515)p valueaCDAI−7.96 (0.33)−7.49 (0.27)−5.74 (0.19)<0.001Patient-reported pain (VAS 0–100)−9.43 (0.69)−7.98 (0.47)−7.70 (0.35)0.074Patient-reported fatigue (VAS 0–100)−7.49 (0.71)−5.87 (0.51)−4.81 (0.36)0.002Patient-reported HAQ−0.16 (0.01)−0.12 (0.01)−0.08 (0.01)<0.001

aEstimated by multiple linear regression model adjusted for age, sex, disease duration, work status, SC nodules, history of hypertension and depression, BL CDAI, BL patient-reported pain and BL fatigue (factors that were identified a priori based on clinical experience or that differed significantly by line of therapy); p values reflect ANOVA overall test of differences across lines of therapy.

VAS=visual analogue scale.

Acknowledgements:

Professional medical writing and editorial assistance was provided by Claire Line, PhD, at Caudex and was funded by Bristol Myers Squibb. The poster was a collaborative effort between Corrona and Bristol Myers Squibb, with financial support provided by Bristol Myers Squibb. This study was sponsored by Corrona, LLC. Corrona is supported through contracted subscriptions with multiple pharmaceutical companies.

Disclosure of Interests:

Leslie Harrold Consultant of: AbbVie, Bristol Myers Squibb, Genentech/Roche, Grant/research support from: Pfizer, Keith Wittstock Employee of: Bristol Myers Squibb, Sheila Kelly Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb, Sang Hee Park Employee of: Bristol Myers Squibb, Xue Han Employee of: Bristol Myers Squibb, Ying Shan: None declared, Carla Roberts-Toler: None declared, Nicole Middaugh: None declared, Vadim Khaychuk Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb

FRI0100 COMPARISON OF PATIENTS (PTS) WITH RHEUMATOID ARTHRITIS (RA) AMONG DISEASE ACTIVITY CATEGORIES AFTER 6 MONTHS OF TREATMENT WITH A TUMOUR NECROSIS FACTOR INHIBITOR (TNFI): RESULTS FROM THE CORRONA® RA REGISTRY

Background:

Targeting remission (REM) or low disease activity (LDA) is a widely accepted treatment strategy for RA. However, there are limited data on the proportion of pts who achieve these targets, or remain in moderate (MDA) or high disease activity (HDA) following advanced therapy.

Objectives:

To estimate the proportion of RA pts in disease activity states (REM, LDA, MDA, and HDA) who were biologic-naïve at initiation and had continuous treatment with a TNFi for 6–12 months in the Corrona RA registry.

Methods:

Eligible pts were aged ≥18 years, biologic-naïve, initiated TNFi treatment between January 1, 2010 and July 31, 2019, and had continuous use of a TNFi for 6–12 months. Disease activity was defined based on Clinical Disease Activity Index (CDAI) at the visit closest to 6-month follow-up: REM, ≤2.8; LDA, >2.8–10; MDA, >10–22; and HDA, >22. Disease characteristics, disease activity measures, and pt-reported outcomes (PROs) were reported at TNFi initiation and at the 6-month follow-up visit.

Results:

2586 biologic-naïve pts who initiated a TNFi and had continuous use for 6–12 months were included. At TNFi initiation, 167 (6%) were in REM, 479 (19%) had LDA, 907 (35%) had MDA, and 1033 (40%) had HDA. After 6–12 months of treatment, 563 (21.8%) were in REM, 923 (35.7%) had LDA, 674 (26.1%) had MDA, and 426 (16.5%) had HDA. Pts with HDA/MDA at 6–12 months were more likely to have a history of hypertension (32.7% HDA; 34.0% MDA; vs 23.6% REM) and had higher mean body mass index (BMI) (30.9 HDA; 31.1 MDA; vs 29.0 REM) at baseline compared with pts in REM. Disease activity measures and PROs were worse in pts with MDA and HDA vs LDA and REM after 6–12 months (Table). Pt Global Assessment was higher than Physician Global Assessment across all groups.

Conclusion:

While 57.4% of pts who initiated a TNFi experienced a favorable outcome, >40% required additional or alternative intervention to achieve REM/LDA. Pts who remained in MDA/HDA continued to have an inadequate response to TNFi (as measured by disease activity measures and PROs) after 6–12 months of treatment compared with those who achieved REM/LDA.

Table

Summary of disease activity measures and PROs in previously biologic-naïve pts at the 6–12-month follow-up visit, stratified by disease activity category at the 6–12-month follow-up visit

Characteristics at 6–12 months, mean (standard deviation)Disease activity category at 6–12 monthsREM (n=563)LDA (n=923)MDA (n=674)HDA (n=426)CDAI1.2 (0.8)6.2 (2.1)15.4 (3.4)32.7 (9.2)Tender joint count (28)0.1 (0.3)1.0 (1.3)4.3 (3.3)13.4 (7.0)Swollen joint count (28)0.1 (0.3)1.1 (1.6)4.0 (3.6)9.1 (5.9)C-reactive protein6.4 (22.7)7.0 (10.6)11.1 (19.9)12.6 (22.1)Modified health assessment questionnaire0.1 (0.2)0.3 (0.4)0.5 (0.5)0.8 (0.5)Pt global assessment6.6 (6.8)28.6 (20.9)43.7 (25.7)58.0 (22.7)Physician global assessment3.6 (4.3)12.1 (10.4)27.4 (15.9)44.9 (19.8)Pt pain assessment8.7 (11.0)30.3 (23.5)46.1 (27.0)59.9 (24.4)Pt fatigue assessment15.7 (19.2)34.5 (26.6)48.3 (28.0)59.4 (27.5)Morning stiffness (min)16.5 (36.5)55.4 (146.3)96.9 (197.5)143.6 (260.0)

Disclosure of Interests:

Joel M Kremer Shareholder of: May own stocks and opinions, Grant/research support from: Research and consulting fees from AbbVie Inc., Consultant of: AbbVie, Amgen, BMS, Genentech, Inc., Gilead, GSK, Lilly, Pfizer, Regeneron and Sanofi, Employee of: Corrona, LLC employee, Anne Winkler Consultant of: AbbVie, Pfizer, and Novratis, Speakers bureau: AbbVie, Janssen, Sanofi, Genentech, Celgene, Eli Lilly, and Novartis., Laura Anatale-Tardiff Employee of: Corrona, LLC employee, Robert McLean Employee of: Corrona, LLC, Ying Shan Employee of: Corrona, LLC employee, Page Moore Employee of: Corrona, LLC employee, Namita Tundia Shareholder of: May own stocks and options, Employee of: AbbVie employee, Jessica Suboticki Shareholder of: AbbVie Inc., Employee of: AbbVie Inc., John Tesser Consultant of: Sanofi/Regeneron, Speakers bureau: Sanofi/Regeneron

Dimethyl sulfoxide, a potent oral radioprotective agent, confers radioprotection of hematopoietic stem and progenitor cells independent of apoptosis

In mass casualty events involving radiation exposure, there is a substantial unmet need for identifying and developing an orally bioavailable agent that can be used to protect the hematopoietic stem cell pool and regenerate hematopoiesis after radiation injury. Dimethyl sulfoxide (DMSO), a free-radical scavenger, has shown therapeutic benefits in many preclinical and clinical studies. This study investigates the radioprotective effects of DMSO on oral administration. Single dose of oral DMSO administrated before irradiation conferred 100% survival of C57BL6/J mice receiving otherwise lethal as well as super-lethal radiation dose, with wide radioprotective time frame (from 15min to 4h). Oral DMSO not only protected radiation-induced acute hematopoietic stem and progenitor cell (HSPC) injury, but also ameliorated long-term BM suppression following irradiation in mice. Mechanistically, DMSO directly protected HSPC survival after irradiation in vitro and in vivo, whereas no radioprotective effect was seen in MLL-AF9-induced leukemia cells. Unexpectedly, DMSO treatment did not inhibit radiation-induced HSPC apoptosis, and the HSPC survival from Trp53-and PUMA-deficient mice after irradiation was also protected by DMSO. In conclusion, our findings demonstrate the radioprotective efficacy of oral DMSO. Given its oral efficacy and little toxicity, DMSO is an attractive candidate for human use in a wide variety of settings, including nuclear accidents and medical radiation.

P-type laser-doped WSe2/MoTe2 van der Waals heterostructure photodetector

Van der Waals heterostructures (vdWHs) based on two-dimensional (2D) materials are being studied extensively for their prospective applications in photodetectors. As the pristine WSe₂/MoTe₂ heterostructure is a type I (straddling gap) structure, it cannot be used as a photovoltaic device theoretically, although both WSe₂ and MoTe₂ have excellent photoelectric properties. The Fermi level of p-doped WSe₂ is close to its valence band. The p-doped WSe₂/MoTe₂ heterostructure can perform as a photovoltaic device because a built-in electric field appears at the interface between MoTe₂ and p-doped WSe₂. Here, a 633 nm laser was used for scanning the surface of WSe₂ in order to obtain the p-doped WSe₂. x-ray photoelectron spectroscopy (XPS) and electrical measurements verified that p-type doping in WSe₂ is produced through laser treatment. The p-type doping in WSe₂ includes substoichiometric WO_x and nonstoichiometric WSe_x. A photovoltaic device using p-doped WSe₂ and MoTe₂ was successfully fabricated. The band structure, light-matter reactions, and carrier-transport in the p-doped WSe₂/MoTe₂ heterojunction were analyzed. The results showed that this photodetector has an on/off ratio of ≈10⁴, dark current of ≈1 pA, and response time of 72 μs under the illumination of 633 nm laser at zero bias (V _ds = 0 V). The proposed p-doping method may provide a new approach to improve the performance of nanoscale optoelectronic devices.

MOTS-c accelerates bone fracture healing by stimulating osteogenesis of bone marrow mesenchymal stem cells via positively regulating FOXF1 to activate the TGF-β pathway

OBJECTIVE

To elucidate the function of MOTS-c in accelerating bone fracture healing by inducing BMSCs differentiation into osteoblasts, as well as its potential mechanism.

MATERIALS AND METHODS

Primary BMSCs were extracted from rats and induced for osteogenesis. The highest dose of MOTS-c that did not affect BMSCs proliferation was determined by CCK-8 assay. After 7-day osteogenesis, the relative levels of ALP, Bglap, and Runx2 in MOTS-c-treated BMSCs influenced by FOXF1 were examined. ALP staining and alizarin red S staining in BMSCs were performed as well. The interaction between FOXF1 and TGF-β was analyzed by ChIP assay. At last, rescue experiments were performed to uncover the role of FOXF1/TGF-β axis in MOTS-c-induced osteogenesis.

RESULTS

1 μM MOTS-c was the highest dose that did not affect BMSCs proliferation. MOTS-c treatment upregulated the relative levels of ALP, Bglap, and Runx2, and stimulated mineralization ability in BMSCs, which were attenuated by the silence of FOXF1. TGF-β was proved to interact with FOXF1, and its level was positively mediated by FOXF1. The silence of FOXF1 attenuated the accelerated osteogenesis and TGF-β upregulation in BMSCs because of MOTS-c induction, and these trends were further reversed by the overexpression of TGF-β.

CONCLUSIONS

MOTS-c treatment markedly induces osteogenesis in BMSCs. During MOTS-c-induced osteogenic progression, the upregulated FOXF1 triggers the activation of TGF-β pathway, thus accelerating bone fracture healing.

[Correlation between the expression of STOX1 in placenta of patients with early onset preeclampsia]

Objective: To investigate the relationship of STOX1expression and pathogenesis of early onset preeclampsia. Methods: 65 cases of preeclampsia women who delivered in Shanghai Pudong Hospital from October 2015 to June 2018, were recruited, which included 31 cases with early onset preeclampsia (early onset group, gestational week<34 weeks) and 34 patients with late onset preeclampsia (late onset group, gestational week ≥34 weeks). 34 cases women who received caesarean section because of pelvic structural deformities, breech presentation, macrosomia and social factors were included as the control group(gestational week ≥34 weeks) were selected as control group.The expression and localization of STOX1 mRNA and protein in placenta of three groups of maternal were evaluated by immunohistochemistry SP, RT-qPCR and Western blotting. Results: (1) The expression of STOX1 in placenta mainly distributed in the cytoplasm of placental syncytiotrophoblasts, cytotrophoblasts, vascular endothelial and mesenchymal cells, a few in the cell nucleus.The staining intensity of STOX1 in early onset group was significantly stronger than that in late onset group, the staining intensity of the late onset group was similar to that of the control group. The positive expression rates of STOX1protein in early onset group, late onset group and control group were 96.8%(30/31), 70.6%(24/34), 67.6%(23/34) respectively, which was higher in early onset group than that in late onset group(P=0.005). There was no statistical difference of STOX1 level between the late onset group and the control group(P=0.793). (2)Relative expression of STOX1 mRNA in early onset group, late onset group and control group were 0.054 3±0.003 5,0.037 5±0.000 7,0.035 2±0.000 4 respectively, which was significantly higher in early onset group than that in late onset group(P<0.05), while there was no statistical difference between the late onset group and the control group(P>0.05).(3)Relative expression level of STOX1 protein in early onset group, late onset group and control group were 0.78±0.04,0.59±0.020 and 0.54±0.018 respectively, which is higher in early onset group than that in late onset group(P<0.05). There was no statistical difference of STOX1 level between the late onset group and the control group(P>0.05). Conclusions: The pathogenesis of early onset and late onset preeclampsia may be different. Up-regulated expression of STOX1 in placenta may be associated with the pathogenesis of early onset preeclampsia.

[Expression and significance of STOX1 in villi and placenta at different stages of normal gestation]

Objective: To investigate the expression and significance of STOX1 in different stages of gestation villi and placenta. Methods: Totally 137 cases of normal villi and placenta of pregnant women were collected from the Department of Obstetrics of Shanghai Pudong Hospital from October 1(st) 2015 to February 28(th) 2018, including 64 cases of early pregnancy (early pregnancy group) which consists of 32 cases of 5-7(+6) weeks gestation (early pregnancy group A) and 32 cases of 8-11(+3) weeks gestation (early pregnancy group B), 28 cases of 14-26 weeks gestation(middle pregnancy group) and 45 cases of 37-41 weeks gestation (late pregnancy group). The expression and localization of STOX1 mRNA and protein in placenta were evaluated by RT-qPCR, Western blotting and immunohistochemistry. Results: (1)STOX1 was positively expressed in the cytotrophoblasts and syncytiotrophoblasts as well as interstitial and vascular endothelial cells of all groups. (2)STOX1 mRNA expression in each group was significantly different (P<0.05), the lowest was in the early pregnancy group A(0.007 8±0.000 4), which increased along with the progression of gestational age(P<0.05),and reached the highest level in the third trimester(0.064 4±0.001 3). (3)The protein level of STOX1 in different stages of normal pregnancy was 0.53±0.20 in early pregnancy group A;0.62±0.37 in early pregnancy group B;0.70±0.03 in middle pregnancy group and 0.81±0.04 in late pregnancy group respectively; which was positively related with the progression of gestational age (P<0.05). Conclusion: The expressions of STOX1 is gradually increasing along with the normal pregnancy progression, suggesting that it might be involved in proliferation, differentiation and infiltration and (or) apoptosis of trophoblast cells and the development of the placenta.

Dimethyl Sulfoxide Prevents Radiation-Induced Oral Mucositis Through Facilitating DNA Double-Strand Break Repair in Epithelial Stem Cells

PURPOSE

Oral mucositis is one of the most prevalent side effects in patients undergoing radiation therapy for head and neck cancers. Current therapeutic agents such as palifermin recombinant human keratinocyte growth factor and amifostine do not efficiently or fully prevent mucositis. Dimethyl sulfoxide (DMSO), a free-radical scavenger, has shown therapeutic benefits in many preclinical and clinical studies. This study aimed to investigate the efficacy of DMSO in a clinically relevant mouse model of acute, radiation-induced oral mucositis.

METHODS AND MATERIALS

Oral mucositis was induced by a high single and fractioned irradiation of the head and neck area in C57BL/6J mice, and the effects of DMSO (by intraperitoneal injection) were assessed by macroscopic and histopathological examination. Epithelial stem and progenitor cells were analyzed by immunohistochemical staining of p63 and Ki-67, and DNA double-strand breaks (DSBs) were visualized by immunofluorescence detection of γ-H2AX. Tumor xenograft was obtained using CAL-27 cells.

RESULTS

Pretreatment with DMSO protected the oral mucosa from severe acute radiation injury, reduced the extent of radiation-induced weight loss, and had no significant effects on tumor weight in irradiated or nonirradiated xenograft mice. Furthermore, the efficacy of DMSO was superior to that of recombinant human keratinocyte growth factor and amifostine. DMSO treatment prevented the loss of proliferative lingual epithelial stem and progenitor cells upon irradiation. More interestingly, the average levels of γ-H2AX foci were significantly decreased in p63-positive epithelial stem cells at 6 hours, but not at 2 hours, after irradiation, indicating that DMSO facilitated DNA DSB repair rather than suppressing the indirect action of irradiation.

CONCLUSIONS

DMSO prevents the loss of proliferative lingual epithelial stem and progenitor cells upon irradiation by facilitating DNA DSB repair, thereby protecting against radiation-induced mucositis without tumor protection. Given its high efficacy and low toxicity, DMSO could be a potential treatment option to prevent radiation-induced oral mucositis.

[Analysis of 17 cases underwent laparoscopic rectal cancer surgery with transanal natural orifice specimen extraction and resection]

Objective: To study the feasibility, safety and short-term efficacy of total laparoscopic rectal cancer surgery with transanal natural orifice specimen extraction and resection. Methods: From May 2014 to March 2016, 17 patients with rectal carcinoma were treated by total laparoscopic rectal cancer surgery with transanal natural orifice specimen extraction and resection. The clinical data of these patients was collected and retrospectively analyzed to assess the impact of the operation on postoperative recovery time and the incidence of complications. Results: All operations had been successfully accomplished without conversion to open surgery or conversional laparoscopic-assisted surgery . The median operative time was 105 minutes. The median blood loss was 35 ml. The median proximal and distal margin of tumor is 16 cm and 3.5 cm. The median number of lymph nodes harvest is 21, and the median first bowl movement is 43 hours. The hospitalization after operation is 8 days. No patient underwent abdomen hemorrhage or anastomotic leakage. Conclusion: Laparoscopic rectal cancer surgery with transanal natural orifice specimen extraction and resection appears to be feasible, safe and with promising efficacy for selected patients.

Abstract P4-06-09: Addition of a remote genetic counselor to the breast specialist's team improves clinical decision-making

Background: There is a shortage of trained genetic counselors (GC) and often long wait times for appointments, resulting in other specialists frequently ordering genetic testing. However, non-genetic specialists, including breast surgeons, find it difficult to stay current in genetics due to rapid advances in gene discovery, expanded panel offerings, and frequent changes to professional guidelines. We tested a novel model for hereditary cancer risk assessment where breast surgeons had “on demand” access to a remote laboratory-based genetic counselor for peer to peer consultation. In this study we sought to determine the impact this model has on breast surgeons' routinely ordering genetic testing including test identification, ordering patterns, and medical management.

Methods: An IRB approved multi-center prospective study involved 14 community-based breast cancer surgeons experienced with hereditary cancer risk assessment without a genetic counselor as part of their practice. Cases were all discussed with a remote Invitae GC to determine testing eligibility and selection. Physicians had the option to utilize remote GCs to discuss results or to refer to traditional genetic counseling services. Pre and post-test surveys were completed for each patient by the testing physician. To protect patient privacy, a unique case ID was used to link patient test data with identifying data.

Results: A total of 192 patients were evaluated with median age of 52. Risk assessment via BRCAPRO and the Hughes Risk model were performed on 98% of patients by the physicians. 65% of patients met NCCN guidelines for testing. Pathogenic mutations were found in 14% of patients. Breast surgeons changed their test selection 21% of the time after discussion with a GC. They called to discuss results in 47% of cases and medical management changes were incorporated in 15% of these cases based on discussion with a remote GC.

Conclusions: Remote GC provider support assisted physicians in facilitating customized test selection, aided in navigating challenging counseling cases, and impacted clinical management. This service may serve as a viable, effective model for 'on demand' genetic counseling support and may be a novel opportunity to expand genetic testing in a breast surgery setting.

Citation Format: Rosen B, O'Leary E, Shan Y, Pat W, Peter B. Addition of a remote genetic counselor to the breast specialist's team improves clinical decision-making [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-06-09.

eEF-2 kinase is a critical regulator of Warburg effect through controlling PP2A-A synthesis

Cancer cells predominantly metabolize glucose by glycolysis to produce energy in order to meet their metabolic requirement, a phenomenon known as Warburg effect. Although Warburg effect is considered a peculiarity critical for survival and proliferation of cancer cells, the regulatory mechanisms behind this phenomenon remain incompletely understood. We report here that eukaryotic elongation factor-2 kinase (eEF-2K), a negative regulator of protein synthesis, has a critical role in promoting glycolysis in cancer cells. We showed that deficiency in eEF-2K significantly reduced the uptake of glucose and decreased the productions of lactate and adenosine triphosphate in tumor cells and in the Ras-transformed mouse embryonic fibroblasts. We further demonstrated that the promotive effect of eEF-2K on glycolysis resulted from the kinase-mediated restriction of synthesis of the protein phosphatase 2A-A (PP2A-A), a key factor that facilitates the ubiquitin-proteasomal degradation of c-Myc protein, as knockdown of eEF-2K expression led to a significant increase in PP2A-A protein synthesis and remarkable downregulation of c-Myc and pyruvate kinase M2 isoform, the key glycolytic enzyme transcriptionally activated by c-Myc. In addition, depletion of eEF-2K reduced the ability of the transformed cells to proliferate and enhanced the sensitivity of tumor cells to chemotherapy both in vitro and in vivo. These results, which uncover a role of the eEF-2K-mediated control of PP2A-A in tumor cell glycolysis, provide new insights into the regulation of the Warburg effect.

Efficient oxygen electroreduction over ordered mesoporous Co–N-doped carbon derived from cobalt porphyrin

High-performance self-supported Co–N-doped carbon electrocatalyst for ORR with comparable activity to Pt/C in both acidic and alkaline media was prepared.

Lentivirus-mediated RNA interference of myostatin gene affects MyoD and Myf5 gene expression in duck embryonic myoblasts

The aim of this study was to construct lentivirus-mediated short hairpin RNA (shRNA) vectors targeting the duck MSTN gene and investigate whether these vectors can affect the development of duck primary cultured embryonic myoblasts. MSTN mRNA levels in the myoblasts were detected using quantitative real-time polymerase chain reaction (PCR), cell proliferation was assessed by MTT assays and cell differentiation was assayed by photography. MSTN mRNA levels in PLL3.7-MSTN-shRNA1, PLL3.7-MSTN-shRNA2 and PLL3.7-MSTN-shRNA3 lentivirus-mediated shRNA groups were reduced by 61.6%, 76.9% and 79.1%, respectively, compared to control cells. Down-regulation of MSTN in duck embryonic myoblasts stimulated cell proliferation and inhibited differentiation, accompanied by a greater than twofold down-regulation of MyoD expression and up-regulation of Myf5 expression. These results revealed that silencing of MSTN changes the development of duck embryonic myoblasts by regulating the expression level of MyoD and Myf5 genes.

Evaluation of improved γ-aminobutyric acid production in yogurt using Lactobacillus plantarum NDC75017

Most γ-aminobutyric acid (GABA)-producing microorganisms are lactic acid bacteria (LAB), but the yield of GABA is limited in most of these GABA-producing strains. In this study, the production of GABA was carried out by using Lactobacillus plantarum NDC75017, a strain screened from traditional fermented dairy products in China. Concentrations of substrate (l-monosodium glutamate, L-MSG) and coenzyme (pyridoxal-5-phosphate, PLP) of glutamate decarboxylase (GAD) and culture temperature were investigated to evaluate their effects on GABA yield of Lb. plantarum NDC75017. The results indicated that GABA production was related to GAD activity and biomass of Lb. plantarum NDC75017. Response surface methodology was used to optimize conditions of GABA production. The optimal factors for GABA production were L-MSG at 80 mM, PLP at 18 μM, and a culture temperature of 36 °C. Under these conditions, production of GABA was maximized at 314.56 mg/100 g. Addition of Lb. plantarum NDC75017 to a commercial starter culture led to higher GABA production in fermented yogurt. Flavor and texture of the prepared yogurt and the control yogurt did not differ significantly. Thus, Lb. plantarum NDC75017 has good potential for manufacture of GABA-enriched fermented milk products.

Combination of adenoviruses expressing melanoma differentiation-associated gene-7 and chemotherapeutic agents produces enhanced cytotoxicity on esophageal carcinoma

We examined the combinatory antitumor effects of adenoviruses expressing human mda-7/IL-24 gene (Ad-mda-7) and chemotherapeutic agents on nine kinds of human esophageal carcinoma cells. All the carcinoma cells expressed the melanoma differentiation-associated gene-7/interleukin-24 (MDA-7/IL-24) receptor complexes, IL-20R2 and either IL-20R1 or IL-22R1, and were susceptible to Ad-mda-7, whereas fibroblasts were positive only for IL-20R2 gene and resistant to Ad-mda-7-mediated cytotoxicity. Sensitivity of these esophageal carcinoma cells to Ad-mda-7 was however lower than that to Ad expressing the wild-type p53 gene. We thereby investigated a possible combination of Ad-mda-7 and anticancer agents and found that Ad-mda-7 with 5-fluorouracil (5-FU), cisplatin, mitomycin C or etoposide produced greater cytotoxic effects than those by Ad-mda-7 or the agent alone. Half-maximal inhibitory concentration values of the agents in respective cells were decreased by the combination with Ad-mda-7. Cell cycle analyses showed that Ad-mda-7 and 5-FU increased G2/M-phase and S-phase populations, respectively, and the combination augmented sub-G1 populations. Ad-mda-7-treated cells showed cleavages of caspase-8, -9 and -3 and poly (ADP-ribose) polymerase, but the cleavage levels were not different from those of the combination-treated cells. Ad-mda-7 treatments upregulated Akt phosphorylation but suppressed IκB-α levels, whereas 5-FU treatments induced phosphorylation of p53 and extracellular signal-regulated protein kinases 1 and 2. Molecular changes caused by the combination were similar to those by Ad-mda-7 treatments, but the Ad-mda-7-mediated upregulation of Akt phosphorylation decreased with the combination. These data collectively suggest that Ad-mda-7 induced apoptosis despite Akt activation and that the combinatory antitumor effects with 5-FU were produced partly by downregulating the Ad-mda-7-induced Akt activation.

Imbalance of different types of CD4(+) forkhead box protein 3 (FoxP3)(+) T cells in patients with new-onset systemic lupus erythematosus

The aim of this study was to examine the numbers of CD4(+) CD25(-) forkhead box protein 3 (FoxP3)(+) , CD4(+) CD25(+) FoxP3(+) and CD4(+) CXCR5(+) FoxP3(+) T cells in patients with new-onset systemic lupus erythematosus (SLE). The numbers of CD4(+) CD25(-) FoxP3(+) , CD4(+) CD25(+) FoxP3(+) and CD4(+) CXCR5(+) FoxP3(+) T cells and the concentrations of serum interleukin (IL)-10 in 23 patients and 20 healthy controls (HC) were measured. The potential correlations between CD4(+) FoxP3(+) T cells, serum IL-10 and clinical measures in SLE patients were analysed. In comparison with that in the HC, significantly reduced numbers of CD4(+) CD25(+) FoxP3(+) and CD4(+) CXCR5(+) FoxP3(+) T cells, but increased numbers of CD4(+) CD25(-) FoxP3(+) T cells, were detected, accompanied by significantly lower levels of serum IL-10 in the patients. Stratification analysis indicated the numbers of CD4(+) CD25(+) FoxP3(+) and CD4(+) CXCR5(+) FoxP3(+) T cells and serum IL-10 levels in the patients with seropositive anti-dsDNA were significantly less than that in those with seronegative anti-dsDNA. Treatment with the anti-SLE therapy, particularly with prednisone, leflunomide and methotrexate, significantly improved the imbalance of these types of FoxP3(+) T cells and increased the concentrations of serum IL-10 in the drug-responding patients. The numbers of CD4(+) CD25(+) FoxP3(+) T cells were correlated negatively with the values of SLE disease activity index (SLEDAI), whereas the numbers of CD4(+) CD25(-) FoxP3(+) T cells were correlated positively with the values of SLEDAI, erythrocyte sedimentation rate (ESR) and serum C3. In addition, the concentrations of serum IL-10 were correlated positively with the numbers of CD4(+) CD25(+) FoxP3(+) T cells, but negatively with the values of SLEDAI, serum C3, CRP and ESR in these patients. Our data indicate that the imbalance of different types of FoxP3(+) CD4(+) T cells may contribute to the development of SLE in Chinese patients.

High frequencies of activated B cells and T follicular helper cells are correlated with disease activity in patients with new-onset rheumatoid arthritis

This study aimed to examine the frequency of different subsets of circulating B and T follicular helper (Tfh) cells in patients with new-onset rheumatoid arthritis (RA) and following standard therapies. Twenty-five RA patients and 15 healthy controls (HC) were recruited for characterizing the frequency of CD27⁺, immunoglobulin (Ig)D⁺, CD86⁺, CD95⁺, Toll-like receptor (TLR)-9⁺ B cells and inducible T cell co-stimulator (ICOS) and programmed death 1 (PD-1)-positive Tfh cells and the level of serum interleukin (IL)-21. The potential correlation between the frequency of different subsets of B and Tfh cells and the values of clinical measures in RA patients was analysed. In comparison with HC, significantly higher percentages of circulating IgD⁺ CD27⁻ CD19⁺ naive B, CD86⁺ CD19⁺ and CD95⁺ CD19⁺ activated B, CD3⁺ CD4⁺ CXCR5⁺, CD3⁺ CD4⁺ CXCR5⁺ ICOS⁺, CD3⁺ CD4⁺ CXCR5⁺ PD-1⁺ and CD3⁺ CD4⁺ CXCR5⁺ ICOS⁺ PD-1⁺ Tfh cells but lower IgD⁺ CD27⁺ CD19⁺ preswitch memory B cells were detected, accompanied by significantly higher levels of serum IL-21 in the RA patients. Furthermore, the percentages of CD95⁺ B cells were correlated positively with the frequency of PD-1⁺ Tfh cells, but negatively with ICOS⁺ Tfh cells. The percentages of CD86⁺ B cells and ICOS⁺ Tfh cells were correlated positively with the values of disease activity score 28 (DAS28). Following the drug therapies for 1 month, the percentages of CD86⁺ B and PD-1⁺ Tfh cells were reduced significantly in the drug-responding patients. Our data suggest that activated B and Tfh cells may contribute to the pathogenesis of RA and the frequency of activated B and Tfh cells may be used as biomarkers for evaluating the therapeutic responses of individual patients with RA.

Piperlongumine induces autophagy by targeting p38 signaling

Piperlongumine (PL), a natural product isolated from the plant species Piper longum L., can selectively induce apoptotic cell death in cancer cells by targeting the stress response to reactive oxygen species (ROS). Here we show that PL induces cell death in the presence of benzyloxycarbonylvalyl-alanyl-aspartic acid (O-methyl)-fluoro-methylketone (zVAD-fmk), a pan-apoptotic inhibitor, and in the presence of necrostatin-1, a necrotic inhibitor. Instead PL-induced cell death can be suppressed by 3-methyladenine, an autophagy inhibitor, and substantially attenuated in cells lacking the autophagy-related 5 (Atg5) gene. We further show that PL enhances autophagy activity without blocking autophagy flux. Application of N-acetyl-cysteine, an antioxidant, markedly reduces PL-induced autophagy and cell death, suggesting an essential role for intracellular ROS in PL-induced autophagy. Furthermore, PL stimulates the activation of p38 protein kinase through ROS-induced stress response and p38 signaling is necessary for the action of PL as SB203580, a p38 inhibitor, or dominant-negative p38 can effectively reduce PL-mediated autophagy. Thus, we have characterized a new mechanism for PL-induced cell death through the ROS-p38 pathway. Our findings support the therapeutic potential of PL by triggering autophagic cell death.

Interaction of Sirt3 with OGG1 contributes to repair of mitochondrial DNA and protects from apoptotic cell death under oxidative stress

Sirtuin 3 (Sirt3), a major mitochondrial NAD(+)-dependent deacetylase, targets various mitochondrial proteins for lysine deacetylation and regulates important cellular functions such as energy metabolism, aging, and stress response. In this study, we identified the human 8-oxoguanine-DNA glycosylase 1 (OGG1), a DNA repair enzyme that excises 7,8-dihydro-8-oxoguanine (8-oxoG) from damaged genome, as a new target protein for Sirt3. We found that Sirt3 physically associated with OGG1 and deacetylated this DNA glycosylase and that deacetylation by Sirt3 prevented the degradation of the OGG1 protein and controlled its incision activity. We further showed that regulation of the acetylation and turnover of OGG1 by Sirt3 played a critical role in repairing mitochondrial DNA (mtDNA) damage, protecting mitochondrial integrity, and preventing apoptotic cell death under oxidative stress. We observed that following ionizing radiation, human tumor cells with silencing of Sirt3 expression exhibited deteriorated oxidative damage of mtDNA, as measured by the accumulation of 8-oxoG and 4977 common deletion, and showed more severe mitochondrial dysfunction and underwent greater apoptosis in comparison with the cells without silencing of Sirt3 expression. The results reported here not only reveal a new function and mechanism for Sirt3 in defending the mitochondrial genome against oxidative damage and protecting from the genotoxic stress-induced apoptotic cell death but also provide evidence supporting a new mtDNA repair pathway.

Pennogenin tetraglycoside induces rat myometrial contraction and MLC20 phosphorylation via PLC-IP(3) and RhoA/Rho kinase signaling pathways

BACKGROUND

Total steroidal saponins extracted from the rhizome of Paris polyphylla Sm. var. yunnanensis (TSSPs) have been widely used in China for the treatment of abnormal uterine bleeding. We previously studied the main active constituents of TSSPs and their structure-activity relationships with respect to rat myometrial contractions. Tg (pennogenin tetraglycoside) was identified as one of the active ingredients in TSSPs able to induce rat myometrial contractions. However, the mechanisms underlying the pharmacological actions on uterine activity have not been described clearly.

METHODS

Here Tg was screened for effects on contractile activity in isolated uterine strips from estrogen-primed rats and on MLC20 phosphorylation and related signaling pathways in cultured rat myometrial cells as determined by Western blot. Intracellular calcium ([Ca(2+)](i)) was monitored under a confocal microscope using Fluo-4 AM-loaded myometrial cells.

RESULTS

Tg dose-dependently stimulated rat myometrial contractions as well as MLC20 phosphorylation in vitro, which could be completely suppressed by an inhibitor of myosin light chain kinase (MLCK). Use of Ca(2+) channel blockers and kinase inhibitors demonstrated that Tg-induced myometrial contractions are mediated by activation of the phospholipase C (PLC)-inositol triphosphate (IP3) signaling pathway, resulting in increased MLC20 phosphorylation. Furthermore, Y27632, a specific inhibitor of Rho kinase (ROK), notably suppressed Tg-stimulated myometrial contractions and decreased MLC20 phosphorylation.

CONCLUSIONS

These data provide evidence that rat myometrial contractility induced by Tg results from enhanced MLC20 phosphorylation, while both PLC-IP3 and RhoA/ROK signaling pathways mediate the process. These mechanisms may be responsible for the therapeutic effects of TSSPs on abnormal uterine bleeding.

IL-12 and IL-10 production are differentially regulated by phosphatidylinositol 3-kinase in mast cells

The cellular mechanisms that directly regulate the production of pro- and anti-inflammatory cytokines after lipopolysaccharide (LPS) stimulation in mast cells are currently unresolved. The aim of this study was to clarify the role of phosphatidylinositol 3-kinase (PI3K) in the production of IL-12 and IL-10 in mouse bone marrow-derived mast cells (BMMCs), stimulated with Escherichia coli-derived LPS. LPS activates the PI3K signalling pathway; analysis of cytokine production following LPS stimulation of BMMCs revealed that inhibition of the PI3K pathway differentially regulated IL-10 and IL-12 syntheses. IL-12 production was enhanced, whereas IL-10 levels were suppressed. Inhibition of LPS-mediated activation of the PI3K pathway resulted in a pronounced reduction of NF-κB activity that was dependent on IκBα phosphorylation. These findings demonstrate a regulatory function for PI3K in modulating IL-10 and IL-12 production in mast cells and provide insight into how engagement of the PI3K pathway affects the induction of key immunoregulatory cytokines that control both qualitative and quantitative aspects of early inflammation.

Recent advances in antiangiogenic agents with VEGFR as target

Angiogenesis is required for invasive tumor growth and metastasis and constitutes an important point in the control of cancer progression. Its inhibition may be a valuable approach to cancer therapy. Antiangiogenic agents are designed to attack the tumor vasculature and cut off the tumor's supply of nutrients. Systemic blockade of angiogenesis has been recently approved for the treatment of several types of human cancers. Antiangiogenic therapy presents various advantages as compared to conventional treatment. Vascular endothelial growth factor (VEGF) is considered to be one of the most important regulators of angiogenesis and a key target in anticancer treatment. VEGF binding to its receptor (VEGFR) leads to cell proliferation and new vascular formation by tyrosine kinase (TK) pathway. VEGF/VEGFR pathway is becoming attractive target for anticancer drug design. It is believed to be important in the control of angiogenesis. Antiangiogenic therapy based on inhibition of VEGFR was reported to be powerful clinical strategies. In this review, the authors describe the existing literature regarding VEGFR inhibitors in the last few years. We attempt to cover all essential publications on the medicinal chemistry in terms of chemical structure, pharmacological profile and structure-activity relationships.