Hyalinizing Clear Cell Carcinoma in the Sphenoid Sinus.

ABSTRACT: A 39-year-old man presented with a 1-month history of headaches. Imaging revealed a mass with extensive destruction. T2-weighted imaging displayed mixture of low and sponge-like high intensities and also dark area, with FDG PET/CT showing uneven but intense accumulation. Biopsy confirmed EWSR1 rearrangement, and hyalinizing clear cell carcinoma (HCCC) was diagnosed. HCCC, recently renamed from clear cell carcinoma in the fifth edition of the World Health Organization Classification of Head and Neck Tumors, is a rare tumor. This case describes the features of T2-weighted imaging and FDG PET patterns in HCCC, possibly contributing to their consideration in the differential diagnosis.

Less nephrotoxicity of paclitaxel and ifosfamide plus nedaplatin for refractory or relapsed germ cell tumors in patients with impaired renal function.

OBJECTIVES: To determine the safety and efficacy of the combined regimen of paclitaxel and ifosfamide plus nedaplatin for patients with refractory or relapsed germ cell tumors and impaired renal function. METHODS: Of a total of 68 patients who received paclitaxel, ifosfamide and nedaplatin chemotherapy for germ cell tumors, those with an estimated glomerular filtration rate <60 mL/min/1.73 m2 before paclitaxel, ifosfamide and nedaplatin treatment were defined as having renal dysfunction. The combination chemotherapy regimen included paclitaxel (210 mg/m2 on day 1) and ifosfamide (1.2 g/m2 on days 2-6) with nedaplatin (100 mg/m2 on day 2) on a 3-week cycle. RESULTS: A total of 10 patients had renal dysfunction with a median estimated glomerular filtration rate of 49.97 mg/mL/1.73 m2 (range 31.7-57.5 mg/mL/1.73 m2 ). Paclitaxel, ifosfamide and nedaplatin chemotherapy was given as second-line therapy in four patients, third-line in four and fourth-line or later in two. Patients with impaired renal function received pretreatment of a median of 5.5 cycles of platinum-based chemotherapy (range 3-11 cycles) with a median cisplatin dose of 550 mg/m2 . The patients were given two to six cycles of paclitaxel, ifosfamide and nedaplatin chemotherapy with no dose reduction, with an overall response rate of 60%. Chemotherapy-induced kidney dysfunction was not observed in any patient with decreased renal function. Furthermore, there was no difference in the frequency of adverse events between patients with renal dysfunction (estimated glomerular filtration rate <60 mL/min/1.73 m2 ) and those with normal renal function (estimated glomerular filtration rate ≥60 mL/min/1.73 m2 ). CONCLUSIONS: Paclitaxel, ifosfamide and nedaplatin chemotherapy can be considered a safe and effective regimen that results in less nephrotoxicity in germ cell tumor patients with renal dysfunction.

Enhanced lysosomal degradation maintains the quiescent state of neural stem cells.

Quiescence is important for sustaining neural stem cells (NSCs) in the adult brain over the lifespan. Lysosomes are digestive organelles that degrade membrane receptors after they undergo endolysosomal membrane trafficking. Enlarged lysosomes are present in quiescent NSCs (qNSCs) in the subventricular zone of the mouse brain, but it remains largely unknown how lysosomal function is involved in the quiescence. Here we show that qNSCs exhibit higher lysosomal activity and degrade activated EGF receptor by endolysosomal degradation more rapidly than proliferating NSCs. Chemical inhibition of lysosomal degradation in qNSCs prevents degradation of signaling receptors resulting in exit from quiescence. Furthermore, conditional knockout of TFEB, a lysosomal master regulator, delays NSCs quiescence in vitro and increases NSC proliferation in the dentate gyrus of mice. Taken together, our results demonstrate that enhanced lysosomal degradation is an important regulator of qNSC maintenance.

FGFR inhibitor BGJ398 and HDAC inhibitor OBP-801 synergistically inhibit cell growth and induce apoptosis in bladder cancer cells.

In advanced bladder cancer, cisplatin-based chemotherapy has been the standard treatment for many years, but there are many problems in terms of side-effects. Recently, a number of clinical trials using molecular-targeted agents have been conducted, and new therapies are expected that could replace conventional cytotoxic chemotherapy. We herein report that concurrent treatment with fibroblast growth factor receptor (FGFR) inhibitor BGJ398 and the novel histone deacetylase (HDAC) inhibitor OBP-801/YM753/spiruchostatin A synergistically inhibited cell growth and markedly induced apoptosis in high-grade bladder cancer cells. This combination activated caspase-3, -8 and -9, and the pan-caspase inhibitor zVAD-fmk significantly reduced the apoptotic response to the combined treatment. The combination upregulated the expression of Bim, one of the pro-apoptotic molecules. In the present study, Bim siRNA efficiently reduced apoptosis induced by the co-treatment of BGJ398 and OBP-801. Therefore, the apoptosis induced by the combination was shown to be at least partially dependent on Bim. Taken together, these results suggest that the combination of BGJ398 and OBP-801 is a novel high potential therapeutic strategy for muscle-invasive bladder cancer.

A Histone Deacetylase Inhibitor, OBP-801, and Celecoxib Synergistically Inhibit the Cell Growth with Apoptosis via a DR5-Dependent Pathway in Bladder Cancer Cells.

The prognosis of muscle-invasive bladder cancer with metastasis is poor. There have been no therapeutic improvements for many years, and an innovative therapy for muscle-invasive bladder cancer has been awaited to replace the conventional cytotoxic chemotherapy. Here, we show a candidate method for the treatment of bladder cancer. The combined treatment with a novel histone deacetylase (HDAC) inhibitor, OBP-801, and celecoxib synergistically inhibited cell growth and markedly induced apoptosis through the caspase-dependent pathway in high-grade bladder cancer cells. Furthermore, the combined treatment induced expression of death receptor 5 (DR5). We identified that knockdown of DR5 by small interfering RNA (siRNA) significantly suppressed apoptosis by the combined treatment. Therefore, we conjectured that the apoptosis induced by OBP-801 and celecoxib is at least partially dependent on DR5. However, it was interesting that the combined treatment drastically suppressed expression of DR5 ligand, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). These data suggest that there is no involvement of TRAIL in the induction of apoptosis by the combination, regardless of the dependence of DR5. Moreover, xenograft studies using human bladder cancer cells showed that the combined therapy suppressed tumor growth by upregulating expressions of DR5 and Bim. The inhibition of tumor growth was significantly more potent than that of each agent alone, without significant weight loss. This combination therapy provided a greater benefit than monotherapy in vitro and in vivo These data show that the combination therapy with OBP-801 and celecoxib is a potential novel therapeutic strategy for patients with muscle-invasive bladder cancer. Mol Cancer Ther; 15(9); 2066-75. ©2016 AACR.