[Advances in immune checkpoint inhibitors in gastrointestinal cancer]

Currently, immunotherapy is considered as the fourth major modality of cancer treatment except surgery, chemotherapy and radiotherapy. The new therapeutic approach based on immune checkpoint inhibitors is a landmark innovation. Strategies considering checkpoint inhibitors have shown good anti-tumor effect by targeting cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1) or programmed cell death ligand 1 (PD-L1). Moreover, DNA mismatch repair-deficient tumors appear to be potential candidates for these therapies. This review summarizes the discussion and oral presentations in the annual meeting of American Society of Clinical Oncology (ASCO) and ASCO-gastrointestinal cancer (GI) in 2016 and provides an update on immunotherapy in gastrointestinal cancers.

PLGA/TCP composite scaffold incorporating bioactive phytomolecule icaritin for enhancement of bone defect repair in rabbits

Bone defect repair is challenging in orthopaedic clinics. For treatment of large bone defects, bone grafting remains the method of choice for the majority of surgeons, as it fills spaces and provides support to enhance biological bone repair. As therapeutic agents are desirable for enhancing bone healing, this study was designed to develop such a bioactive composite scaffold (PLGA/TCP/ICT) made of polylactide-co-glycolide (PLGA) and tricalcium phosphate (TCP) as a basic carrier, incorporating a phytomolecule icaritin (ICT), i.e., a novel osteogenic exogenous growth factor. PLGA/TCP/ICT scaffolds were fabricated as PLGA/TCP (control group) and PLGA/TCP in tandem with low/mid/high-dose ICT (LICT/MICT/HICT groups, respectively). To evaluate the in vivo osteogenic and angiogenic potentials of these bioactive scaffolds with slow release of osteogenic ICT, the authors established a 12 mm ulnar bone defect model in rabbits. X-ray and high-resolution peripheral quantitative computed tomography results at weeks 2, 4 and 8 post-surgery showed more newly formed bone within bone defects implanted with PLGA/TCP/ICT scaffolds, especially PLGA/TCP/MICT scaffold. Histological results at weeks 4 and 8 also demonstrated more newly mineralized bone in PLGA/TCP/ICT groups, especially in the PLGA/TCP/MICT group, with correspondingly more new vessel ingrowth. These findings may form a good foundation for potential clinical validation of this innovative bioactive scaffold incorporated with the proper amount of osteopromotive phytomolecule ICT as a ready product for clinical applications.

Deletion of estrogen receptor beta accelerates early stage of bone healing in a mouse osteotomy model

This study examined the role of estrogen receptor (ER) beta during mouse femoral fracture healing by employing ER knockout (KO) mice. The fracture healing in KO mice was enhanced in the early stage of neovascularization and the middle stage of endochondral ossification.

INTRODUCTION

This study was conducted to examine the role of ER beta during fracture healing.

METHODS

Female ERbeta knockout (KO) mice (18 weeks old) and age-matched female wild-type (WT) mice underwent open osteotomy on the right femur. They were sacrificed at 1, 2, 4 and 6 weeks post-fracture. The sera and callus samples were subjected to the following analyses: micro-computed tomography (CT)-based angiography, micro-CT evaluation, histological examination, histomorphometry examination, real-time polymerase chain reaction (PCR) analysis, biochemical marker, and mechanical testing.

RESULTS

Micro-CT-based angiography showed that the total vessel volume at the fracture site was larger in the KO group than the WT group at 1 and 2 weeks post-fracture. Micro-CT analysis revealed that the callus volume was significantly higher in the KO group from week 2 to week 4 post-fracture when compared with the WT group consistent with the histological data. Analysis of biochemical markers indicated that circulating P1NP levels in the KO mice were significantly higher than in the WT mice from week 2 to week 4 and that temporal expression of circulating C-terminal telopeptide of type I collagen (CTX) levels was also higher in the KO mice than in the WT mice. These results were consistent with quantitative real-time PCR analysis. The ultimate load, stiffness, and energy to failure were significantly higher in the KO mice than in the WT mice at week 4.

CONCLUSIONS

The fracture healing in KO mice was enhanced in the early stage of neovascularization and the middle stage of endochondral ossification, but not by the end of healing. Blockade of ERbeta can be considered as another therapeutic strategy for osteoporotic fracture and non-union fracture.

Effect of water-soluble P-chitosan and S-chitosan on human primary osteoblasts and giant cell tumor of bone stromal cells

Water-soluble phosphorylated chitosan (P-chitosan) and disodium (1 → 4)-2-deoxy-2-sulfoamino-β-D-glucopyranuronan (S-chitosan) are two chemically modified chitosans. In this study, we found that P-chitosan significantly promotes cell proliferation of both human primary osteoblasts (OBs) and the OB like stromal cell component of the giant cell tumor of bone (GCTB) cells at the concentration from 125 to 1000 µg ml⁻¹ at all time points of 1, 3, 5 and 7 days after treatment. Further investigation of the osteogenic effect of the P-chitosan suggested that it regulates the levels of osteoclastogenic factors, receptor activator of nuclear factor kappa B ligand and osteoprotegerin expression. An interesting finding is that S-chitosan at lower concentration (100 µg ml⁻¹) stimulates cell proliferation while a higher dose (1000 µg ml⁻¹) of S-chitosan inhibits it. The inhibitory effect of S-chitosan on human primary GCT stromal cells was greater than that of OBs (p < 0.05). Taken together, our findings elucidated the osteogenic effect of P-chitosan and the varying effects of S-chitosan on the proliferation of human primary OBs and GCT stromal cells and provided us the rationale for the construction of novel bone repair biomaterials with the dual properties of bone induction and bone tumor inhibition.

Ethanol embolization of auricular arteriovenous malformations: preliminary results of 17 cases

BACKGROUND AND PURPOSE

Because of the relatively rare and extremely varied clinical presentations, arteriovenous malformations (AVMs) involving the auriculae are technically challenging clinical entities to diagnose and, ultimately, manage. The purpose of our study was to present our initial experience of ethanol embolization in a series of 17 patients with auricular AVMs and assess the interim therapeutic outcomes of this method.

MATERIALS AND METHODS

Our study group consisted of 17 patients. Transcatheter arterial embolization and/or direct percutaneous puncture embolization were performed. Pure or diluted ethanol was manually injected. Follow-up evaluation was obtained on the basis of physical examination and angiography at 3- to 4-month intervals and telephone questionnaire at 1-month intervals in all patients.

RESULTS

During the 29 ethanol embolization procedures, the amount of ethanol used ranged from 4 to 65 mL. The obliteration of ulceration, hemorrhage, pain, infection, pulsation, and bruit in most of the patients was obtained. The reduction of redness, swelling, and warmth was achieved in all of the patients, and 15 of the patients achieved downstaging of the Schobinger status. According to the angiographic findings, AVMs were devascularized 100% in 3 patients, 76% to 99% in 5 patients, 50% to 75% in 6 patients, and less than 50% in 3 patients. The most common complications were reversible necrosis and blister.

CONCLUSIONS

Ethanol embolization has proved efficacious and safe in the treatment of auricular AVMs and has the potential to be accepted as the primary mode of therapy in the management of these lesions.

Ethanol embolization of arteriovenous malformations of the mandible

BACKGROUND AND PURPOSE

Absolute ethanol was reported as an effective embolization of arteriovenous malformations (AVMs), but its use to treat AVMs in the mandible is not yet well established. Here, we present our clinical experience on treatment of mandibular AVMs with absolute ethanol.

MATERIALS AND METHODS

Eight consecutive patients with symptomatic AVMs of the mandible between August 2007 and September 2008 were enrolled in this study group. Among them, 6 patients underwent direct puncture embolization with absolute ethanol combined with coils, 1 patient underwent direct puncture embolization with absolute ethanol only, and the last patient had transarterial embolization with absolute ethanol alone. The use of coils decreased the flow and volume of the nidus, and then absolute ethanol embolization was directed against and obliterated the nidus completely. The procedure was performed with the patients under general anesthesia with nasal intubation, and the vital signs of the patients were constantly monitored during the injection of absolute ethanol. The total amount of absolute ethanol used per session was less than 1 mL/kg of body weight.

RESULTS

A total of 11 ethanol embolizations were performed on 8 patients, including 3 sessions with transarterial microcatheterization and 8 with direct puncture embolization. A venogram and control arteriogram performed immediately after the procedure were both obtained, which documented a significant thrombosis of the lesion in all patients. Follow-up examinations revealed that oral bleeding was controlled, the expansion of the external jugular vein in 5 cases was obliterated, and satisfactory shrinkage of the facial swelling was achieved. Follow-up angiography (mean, 4.2 months) was available in 4 patients, and there was no angiographic recurrence of the lesions. There were 3 cases with minor complications.

CONCLUSIONS

On the basis of our experience, treatment of AVMs in the mandible with absolute ethanol is a feasible, safe, and highly effective method.

[Effect of badoushuang on progressive glomerular sclerosis in rats with 7/8 nephrectomy]

Effect of Badoushuang (Semen crotonis pulveratum) was studied in the 7/8 nephrectomied rats, which we could establish as progressive glomerulosclerosis model in rats (Jap J Nephrol 32: 127, 1990). Badoushuang was administered into rats orally 60 mg/kg/day every day after 7/8 nephrectomy. As controls 7/8 nephrectomied rats were used. No adverse effect of Badoushuang were noted during 8 weeks of observation periods. Administration of Badoushuang, in rats with a remnant kidney, decreases urinary protein and lowers blood pressure, keeps creatinine clearance and lowers serum creatinine level and BUN. Morphologically glomerular hypertrophy, crescent formation and sclerosis were less in experimental treated rats. These results suggest Badoushuang ameliorates the progressive kidney disease of rats with subtotal renal ablation. Further study is necessary to clarify the effect of Basoushuang on progressive glomerular sclerosis.