Cisplatin-induced acute renal failure in mice is mediated by chymase-activated angiotensin-aldosterone system and interleukin-18.

Mechanism(s) of cisplatin-induced acute renal failure, as manifested by increases in blood urea nitrogen and creatinine, was evaluated in relation to production and activation of endogenous mediator(s) in mice. In interleukin (IL)-18-deficient (IL-18KO) mice, cisplatin failed to induce acute renal failure. Administration of recombinant IL-18 prior to cisplatin restored acute renal failure in IL-18KO mice. Accumulation of cisplatin in the kidney was not different in IL-18KO and wild-type (WT) mice, but, clearance of cisplatin was more rapid in IL-18KO mice than in WT mice. Cisplatin increased serum levels of aldosterone and angiotensin II in WT mice, but only angiotensin II levels in IL-18 KO mice. Administration of IL-18 augmented plasma levels of aldosterone and angiotensin II in WT mice. Eplerenone, an aldosterone receptor blocker, TY-51469, a chymase inhibitor and PD123319, a selective angiotensin II type 2 (AT2) receptor antagonist, but not benazepril, an angiotensin-converting enzyme inhibitor, and candesartan, a selective angiotensin II type 1 (AT1) receptor antagonist improved acute renal failure caused by cisplatin, confirming involvement of IL-18, aldosterone and angiotensin II in cisplatin-induced, chymase-dependent acute renal failure in mice. These results show that IL-18, aldosterone and angiotensin II synergistically act to prolong the accumulation of cisplatin in the kidney, leading to acute renal failure. Combined therapy with inhibitors for chymase and aldosterone receptors or AT2 receptors might reduce acute renal failure induced by cisplatin.

Keratotic basal cell carcinoma of the tongue: case report.

Basal cell carcinoma (BCC) is the most common skin cancer. Its occurrence in the oral mucosa is extremely rare. We report the clinical course of BCC arising in the inferior surface of the tongue. We performed a super selective intra-arterial chemotherapy combined with radiotherapy for this case. Local tumor response showed CR, and no recurrence was seen after the treatment.

Allergy to metal caused by materials used for intermaxillary fixation: case report.

A 21-year-old man with no history of contact allergy developed eczema over his entire body 2 days after he had had intermaxillary fixation (IMF) of a mandibular fracture. Patch testing showed a strong reaction to nickel so the arch bars and wires that had been used for fixation were removed and replaced with resin brackets, elastic bands, and a chin cap. The eczema disappeared 2 days later.

Establishment of nude mouse transplantable model of a human adenoid cystic carcinoma of the oral floor showing metastasis to the lymph node and lung.

Adenoid cystic carcinoma (ACC) is a generally slow-growing but highly malignant salivary gland neoplasm with remarkable capacities for local invasion and lung metastasis. The precise characteristics of ACC are not fully understood because there was no suitable animal model. We have successfully established a new human tumor line (ACCI) derived from ACC of the oral floor, which showed a cribriform pattern histologically and serially transplantable into nude mice. This tumor developed spontaneous metastasis to the neck at the second passage level, and the histological feature changed from ACC to undifferentiated carcinoma (ACCIM). ACCIM caused spontaneous metastasis to the lung at high incidence when transplanted subcutaneously in nude mice. In this study, we examined the characteristics of this interesting human ACC metastatic line. Tumor fragments were subcutaneously transplanted into nude mice and tumor growth was measured at 1-week intervals. Histological and immunohistochemical examinations were performed. As a result, the tumor growth rate of ACCIM increased as compared to that of ACCI, and the PCNA labeling index was elevated. Furthermore, ACCIM produced multiple metastases to lymph nodes and lungs 5 months after transplantation, and all mice died within 6 months. These multiple metastases were also confirmed in orthotopic transplantation to the tongue. RT-PCR analysis revealed that ACCIM expressed human beta-actin, indicating its human origin. From these findings, ACCIM transplanted into nude mice would provide a useful model for investigating the biological behaviour of ACC.