Relationship between arthroscopic findings of synovitis and levels of tumour necrosis factor-alpha and matrix metalloproteinases in synovial lavage fluid from patients with unilateral high mandibular condyle fractures

Arthrocentesis has an effect of washing out inflammatory products that accumulate in the joint compartment of a dysfunctional temporomandibular joint (TMJ). The procedure removes inflammatory cytokines, which are pain-causing substances, for early reduction of TMJ pain and quick recovery of jaw function, thus increasing the possibility of a successful rehabilitation. The aim of this study was to investigate the relationship between arthroscopy synovitis grade in patients with unilateral high condylar fractures and concentrations of the pro-inflammatory cytokines tumour necrosis factor (TNF)-alpha as well as of matrix metalloproteinases (MMPs) in washed-out synovial fluid (SF) samples obtained from those patients. A total of 26 patients with unilateral high condylar fractures who underwent arthrocentesis for a therapeutic purpose were examined. SF samples were collected before performing arthroscopy to determine synovitis grade. The detection rates and concentrations of TNF-alpha and MMPs were determined, and their association with synovitis grade was analysed. TNF-alpha was detected in 23 and MMP-3 in 22 of the TMJs. There was a correlation between synovitis grade and concentration of TNF-alpha in the fracture group. Furthermore, the concentrations of TNF-alpha and MMP-3 were significantly higher as compared to the control group, comprised of TMJs on the non-fracture side of the same patients, while a correlation was also noted between TNF-alpha concentration and synovitis grade in the fracture group. The present findings may provide a biological/biochemical rationale for arthrocentesis as a reasonable treatment modality for high condylar fractures.

Pretreatment of Crude Pancreatic Islets with Mitomycin C (Mmc) Prolongs Islet Graft Survival in a Xenogeneic Rat-To-Mouse Model

In this study, we examined the effect of mitomycin C (MMC) treatment on graft survival and evaluated its efficacy in immunomodulation of islet graft for transplantation. Male WS rats were used as islet donors and streptozotocin-induced diabetic C57BL/6 mice as recipients. The isolated islets were treated with MMC at concentrations of 0, 0.1, 1, 3.2, 10, 32, 100, 320, and 1000 μg/mL for 30 min, and were cultured for 20 h. Then, 300–400 islets were transplanted into the renal subcapsular space of diabetic mice. Significant prolongation of graft survival was obtained when the islets were treated with MMC at a concentration of 10, 32, or 100 μg/mL (MST 23 ± 7.4, 17.5 ± 5.4, 29.6 ± 9.7 days: p < 0.003, p < 0.012, p < 0.001, respectively, vs. 12.3 ± 2.7 days for culturing alone). Islets treated with MMC at a concentration of 320 μg/mL or more failed to restore normoglycemia in the diabetic recipient mice after transplantation. Viability of islets incubated with doses up to 100 μg/mL, assessed under the confocal microscope after propidium iodide and Hoechst 33342 staining, was maintained well comparable to that of freshly isolated islets, while those treated at 320 μg/mL was significantly decreased. Thus, a therapeutic window for MMC efficacy was found at concentrations from 10 μg/mL to 100 μg/mL. This modality is simple and effective and underlying molecular mechanisms need to be determined in the future.

Endo-α-Mannosidase-Catalyzed Transglycosylation

In order for facilitating the synthesis of oligosaccharides, transglycosylation reactions mediated by glycoside hydrolases have been studied in various contexts. In this study, we examined the transglycosylating activity of a Golgi endo-α-mannosidase. We prepared various glycosyl donors and acceptors, and recombinant human Golgi endo-α-mannosidase and its various mutants were expressed. The enzyme was able to mediate transglycosylation from α-glycosyl-fluorides. Systematic screening of various point mutants revealed that the E407D mutant had excellent transglycosylation activity and extremely low hydrolytic activity. Substrate specificity analysis revealed that minimum motif required for glycosyl acceptor is Manα1- 2Man. The synthetic utility of the enzyme was demonstrated by generation of a high-mannose-type undecasaccharide (Glc₁ Man₉ GlcNAc₂ ).

Abstract P4-21-08: A phase I/II of S-222611, a reversible EGFR and HER2 inhibitor, combined with trastuzumab +/- chemotherapy in patients with HER2-positive metastatic breast cancer

Background: S-222611, an oral, reversible EGFR and HER2 inhibitor, has been shown to be well-tolerated as monotherapy at a dose of 800mg daily with good anti-tumor activity in patients previously treated with other anti-HER2-based regimens. This study evaluated the tolerability and safety of daily oral administration of S-222611 (S) in combination with trastuzumab (T), trastuzumab + vinorelbine (T+V) and trastzumab + capecitabine (T+C) in HER2-positive (HER2+) metastatic breast cancer (MBC) with or without brain metastases.

Methods: This study was performed as a 3+3 dose escalation followed by expansion to examine the tolerability and safety of S in combination with T, T+V and T+C in Arms A, B and C, respectively. S was administered orally once daily, starting at a dose of 400mg in Arm A, and 200mg in Arms B and C. The dosing of T was 8mg/kg loading followed by 6mg/kg or fixed dose of 600mg subcutaneously every 21 days as recommended. V was administered at 60mg/m2 orally on Day 1 and 8 of a 21-day cycle, and C 1000mg/m2 orally daily for 14 days followed by a 7-day rest period. All patients had HER2+ MBC and were required to have progressed following at least one prior line of anti-HER2 therapy. Prior treatments with V and C were permitted. Anti-diarrhea prophylaxis with loperamide was not required.

Results: A total of 45 patients were enrolled. All patients had received prior anti-tumor regimens including T (n=45), T-DM1 (n=26), pertuzumab (n=9) and lapatinib (n=12). The clinically recommended doses of S at which most adverse events were manageable,were determined as:600mg in Arm A, 200mg in Arm B and 400mg in Arm C. Dose limiting toxicities included Grade 3 diarrhea for Arm A; and Grade 4 neutropenia, Grade 3 Hypokalemia and Hypophosphatemia for Arm B. As of 13 May 2016, treatment is ongoing in 2 patients. No other Grade 4 AEs related to S-222611 have been observed. Grade 3 bilirubin elevation was observed in 5/45 patients, probably due to transporter (UGT1A1) inhibition, while no G3/4 liver dysfunction was reported. RECIST partial responses (PR) were observed in 6 of 9 patients in Arm A and 5 of 9 patients in Arm C, at respective clinically recommended doses. Nine of 45 patients had brain metastases; 4 of these patients showed RECIST PR including an intracranial tumor response in one patient (400mg in Arm C) who had prior treatments with paclitaxel, T+C, T-DM1 and V after diagnosis of BM.

Conclusions: The clinically recommended doses of S-222611 combined with T, T +V and T+C were determined for further clinical studies. Clinical benefit (PR and SD &gt;6 month) was seen with each combination even in heavily pre-treated HER2+ MBC patients.

Summary of the safety and efficacy of S-222611 (S) combination. Dose (mg)nDLT (1st cycle)G3 Diarrhea during study (N of patients)RECIST tumor response, PR n/ SD ≥6M nORR n (%)CBR n (%)Arm A: S + T4005010/10/5 (0%)1/5 (20%)Arm A: S + T6009036/06/9 (67%)6/9 (67%)Arm A: S + T8007141/11/7 (14%)2/7 (29%)Arm B: S + T + V2005020/40/5 (0%)4/5 (80%)Arm B: S + T + V4002211/01/2 (50%)1/2 (50%)Arm C: S + T + C2004010/10/4 (0%)1/4 (25%)Arm C: S + T + C4009025/05/9 (56%)5/9 (56%)Arm C: S + T + C6004022/12/4 (50%)3/4 (75%)

Citation Format: Rafii S, Macpherson I, Baird R, Saggese M, Spiliopoulou P, Kumar S, Italiano A, Bonneterre J, Campone M, Cresti N, Posner J, Takeda Y, Arimura A, Spicer J. A phase I/II of S-222611, a reversible EGFR and HER2 inhibitor, combined with trastuzumab +/- chemotherapy in patients with HER2-positive metastatic breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-21-08.

The pattern of GPI-80 expression is a useful marker for unusual myeloid maturation in peripheral blood

Myeloid-derived suppressor cells (MDSCs) have a wide spectrum of immunosuppressive activity; control of these cells is a new target for improving clinical outcomes in cancer patients. MDSCs originate from unusual differentiation of neutrophils or monocytes induced by inflammatory cytokines, including granulocyte-colony stimulating factor (G-CSF) and granulocyte-macrophage (GM)-CSF. However, MDSCs are difficult to detect in neutrophil or monocyte populations because they are not uniform cells, resembling both neutrophils and monocytes; thus, they exist in a heterogeneous population. In this study, we investigated GPI-80, a known regulator of Mac-1 (CD11b/CD18) and associated closely with neutrophil maturation, to clarify this unusual differentiation. First, we demonstrated that the mean fluorescence intensity (MFI) of GPI-80 and coefficient of variation (CV) of GPI-80 were increased by treatment with G-CSF and GM-CSF, respectively, using a human promyelocytic leukaemia (HL60) cell differentiation model. To confirm the value of GPI-80 as a marker of unusual differentiation, we measured GPI-80 expression and MDSC functions using peripheral blood cells from metastatic renal cell carcinoma patients. The GPI-80 CV was augmented significantly in the CD16^hi neutrophil cell population, and GPI-80 MFI was increased significantly in the CD33^hi monocyte cell population. Furthermore, the GPI-80 CV in the CD16^hi population was correlated inversely with the proliferative ability of T cells and the GPI-80 MFI of the CD33^hi population was correlated with reactive oxygen species production. These results led us to propose that the pattern of GPI-80 expression in these populations is a simple and useful marker for unusual differentiation, which is related to MDSC functions.

Direct assay for endo-α-mannosidase substrate preference on correctly folded and misfolded model glycoproteins

We previously reported a unique assay system for UDP-glucose glycoprotein glucosyltransferase (UGGT) toward glycoprotein folding intermediates during the folding process. The assay involved the in vitro folding of both high-mannose type oligosaccharyl crambin, which yielded only the correctly folded glycoprotein form (M9-glycosyl-native-crambin), and its mutant, which yielded misfolded glycoproteins (M9-glycosyl-misfolded-crambin), in the presence of UGGT. The process successfully yielded both mono-glucosylated M9-glycosyl-native-crambin (G1M9-glycosyl-native-crambin) and M9-glycosyl-misfolded-crambin (G1M9-glycosyl-misfolded-crambin). Here, we report the use of our in vitro folding system to evaluate the substrate preference of Golgi endo-α-mannosidase against G1M9-native and -misfolded glycoprotein forms. In our assay Golgi endo-α-mannosidase removed Glc-α-1-3-Man unit from G1M9-native and -misfolded-crambins clearly proving that Golgi endo-α-mannosidase does not have specific preference for correctly folded or misfolded protein structure.

Synthesis of misfolded glycoprotein dimers through native chemical ligation of a dimeric peptide thioester

Glycoprotein quality control processes are very important for an efficient production of glycoproteins and for avoiding the accumulation of unwanted toxic species in cells. These complex processes consist of multiple enzymes and chaperones such as UGGT, calnexin/calreticulin, and glucosidase II. We designed and synthesized monomeric and dimeric misfolded glycoprotein probes. Synthetic homogeneous monomeric glycoproteins proved to be useful substrates for kinetic analyses of the folding sensor enzyme UGGT. For a concise synthesis of a bismaleimide-linked dimer, we examined double native chemical ligation (dNCL) of a dimeric peptide-α-thioester. The dNCL to two equivalents of glycopeptides gave a homodimer. The dNCL to a 1 : 1 mixture of a glycopeptide and a non-glycosylated peptide gave all the three possible ligation products consisting of two homodimers and a heterodimer. Both the homodimer bearing two Man9GlcNAc2 (M9) oligosaccharides and the heterodimer bearing one M9 oligosaccharide were found to be good substrates of UGGT.