Durable response to nivolumab rechallenge in a patient with metastatic clear cell renal cell carcinoma.

Introduction: While immune checkpoint inhibitors represent the mainstream treatment for metastatic renal cell carcinoma, a standardized approach following immune checkpoint inhibitors remains unclear. We report a case of metastatic renal cell carcinoma treated with nivolumab rechallenge. Case presentation: A 60-year-old male with metastatic melanoma was referred to the urology division due to right renal cancer. He was undergoing nivolumab treatment for metastatic melanoma. Radical nephrectomy revealed clear cell renal cell carcinoma, pT3a. Two months post-surgery, multiple metastases were identified. Despite subsequent administration of interferon-α, axitinib, and temsirolimus, the metastases progressed. Consequently, nivolumab rechallenge and palliative radiotherapy were initiated, resulting in a durable response for 20 months. However, disease progression occurred, and he died of cancer 4 years after nephrectomy. Conclusion: This is the first report of nivolumab rechallenge in metastatic renal cell carcinoma. Although the utility remains unclear, this case suggests that some patients may benefit from nivolumab rechallenge.

Infiltrative tumor interface with normal renal parenchyma in locally advanced renal cell carcinoma: Clinical relevance and pathological implications.

OBJECTIVES: Locally advanced renal cell carcinoma is considered clinically aggressive, despite heterogeneity in survival outcomes. We investigated the clinical relevance and pathological implications of infiltrative tumor interface with normal renal parenchyma on preoperative imaging in locally advanced renal cell carcinoma. METHODS: A total of 77 patients with locally advanced renal cell carcinoma (≥pT3a Nany M0) who underwent radical or partial nephrectomy (2008-2018) were analyzed. Preoperative dynamic computed tomography images were reviewed to assess radiological infiltrative features. A radiological infiltrative feature was defined as an ill-defined tumor interface with normal renal parenchyma. The tumor interfaces were analyzed histologically and compared with radiological findings. RESULTS: The median tumor size was 6.4 cm. Lymphadenopathy was observed in four patients (5.2%). Clear cell renal cell carcinoma was diagnosed in 66 patients (86%) and Fuhrman grade was 3-4 in 38 patients (49%). A total of 30 patients (39%) showed radiological infiltrative features, which were significantly associated with larger tumor size and higher clinical T stage. The specificity and sensitivity of radiological infiltrative features in predicting pathological renal parenchymal infiltration were 90 and 64%, respectively. During a median follow-up period of 3.8 years, 27 patients (35%) developed cancer recurrences, and six patients (7.8%) died of renal cell carcinoma. Multivariable analysis showed that the presence of radiological infiltrative features was an independent risk factor for cancer recurrence. Cancer recurrence and cancer-specific mortality were significantly stratified by the presence or absence of radiological infiltrative features (P < 0.001 and P = 0.02, respectively). CONCLUSIONS: Locally advanced renal cell carcinoma can show radiological infiltrative features preoperatively, which are significantly associated with unfavorable prognosis. Radiological infiltrative features on preoperative imaging correspond with a high specificity to pathological renal parenchymal infiltration.

Dihydroresveratrol cellobioside and xylobioside as effective melanogenesis activators.

Dihydroresveratrol cellobioside and xylobioside, whose structures were designed based on that of the naturally occurring melanogenesis-controlling agent dihydroresveratrol glucoside, were synthesized via Schmidt glycosylation as the key step. Both analogues stimulated melanogenesis with efficacies comparable to that of 8-methoxypsoralen, a well-known melanogenesis activator. This suggests that diglycosyl modification of the 4'-OH on the dihydroresveratrol skeleton leads to the activation of melanogenesis, both with and without hydroxymethyl groups in the sugar moieties.

Synthesis of dihydroresveratrol glycosides and evaluation of their activity against melanogenesis in B16F0 melanoma cells.

Dihydroresveratrol glucoside 1 isolated from Camellia oleifera and its xyloside derivative 2 were synthesized for the first time in 5 steps from TBS-protected aldehyde 4. Natural product 1 is a potent melanogenesis inhibitor in B16F0 melanoma cells (approximately 40 fold more potent than kojic acid). In contrast, the synthetic product 2 stimulates melanogenesis, suggesting that a single hydroxymethyl group in the glycoside substituent of dihydroresveratrols is responsible for inhibition or activation of melanogenesis.

Tetra-n-butylammonium bromide-water (1/38).

Tetra-n-butylammonium bromide forms the title semi-clathrate hydrate crystal, C16H36N+.Br-.38H2O, under atmospheric pressure. The cation and anion lie at sites with mm symmetry and seven water molecules lie at sites with m symmetry in space group Pmma. Br- anions construct a cage structure with the water molecules. Tetra-n-butylammonium cations are disordered and are located at the centre of four cages, viz. two tetrakaidecahedra and two pentakaidecahedra in ideal cage structures, while all the dodecahedral cages are empty.

Texture change of ice on anomalously preserved methane clathrate hydrate.

We used a confocal scanning microscope to observe growth and texture change of ice due to the dissociation of methane gas clathrate hydrate (CH(4) hydrate). The experiments were done under CH(4) gas atmospheric pressure and isothermal conditions between 170 and 268 K. Above 193 K, the dissociation of CH(4) hydrate resulted in many small ice particles that covered the hydrate surface. These ice particles had roughly the same shape and density between 193 and 210 K. In contrast, above 230 K the ice particles developed into a sheet of ice that covered the hydrate surface. Moreover, the measured release of CH(4) gas decreased when the sheet of ice formed at the surface of the hydrate. These findings can explain the anomalous preservation behavior of CH(4) hydrate; that is, the known increase of storage stability of CH(4) hydrate above 240 K is likely related to the formation of the ice that we observed in the experiments.