Transformation of pleomorphic adenoma to carcinoma ex pleomorphic adenoma of the parotid gland is independent of p53 mutations.

BACKGROUND AND OBJECTIVES: This retrospective study was performed to evaluate the status of p53 in pleomorphic adenomas and carcinomas ex pleomorphic adenoma in the parotid gland. As loss or mutation of p53 can cause malignant transformation, the possible degeneration of pleomorphic adenomas to carcinomas ex pleomorhic adenoma was investigated by mutational analysis. METHODS: Twenty-five Patients including 14 patients with pleomorphic adenomas and 11 patients with carcinoma ex pleomorphic adenoma of the parotid gland were examined for p53 status. DNA was extracted out of paraffin-embedded tissue and PCR was performed for the coding exons 2-11. Denaturing gradient gel electrophoresis (DGGE) was carried out for mutational analysis and DNA sequencing was performed in case of a suspected mutation. RESULTS: Fourteen pleomorphic adenomas and 11 carcinomas ex pleomorphic adenoma were screened for p53 status and potent mutations. Subsequent sequencing of the distinct exons showed no mutation. CONCLUSION: We could not detect mutations of p53 neither in benign nor malignant parotid tumors and we therefore assume that p53 plays no role in the transformation from pleomorphic adenoma to carcinoma ex pleomorphic adenoma.

Analysis of 60 patients after tympanotomy and sealing of the round window membrane after acute unilateral sensorineural hearing loss.

OBJECTIVE: This retrospective study was performed to evaluate the effectiveness of tympanotomy and sealing of the round window membrane after unilateral acute hearing loss. DESIGN: All patients presenting idiopathic sudden hearing loss, acoustic, or barotrauma were treated with prednisolone and caroverine. Thirty-six patients had a mean pure tone hearing level worse than 70 dB. Recovery was defined as improvement of hearing threshold for 5 frequencies (250, 500, 1000, 2000, and 4000 Hz). If hearing did not improve after conservative treatment, an exploratory tympanotomy and sealing of the round window membrane were suggested. In the last 8 years, 60 patients with idiopathic sudden hearing loss, acoustic, or barotrauma underwent tympanotomy. RESULTS: In 40 patients, we observed improvement of hearing level up to complete remission. In 20 patients, no change could be detected. In the group of patients with documented barotrauma, 12 patients showed improved hearing levels. Of 37 patients with idiopathic sudden hearing loss, 26 had an improved hearing after surgery. Most patients were operated on within 14 days (range, 1-60 days), but time of surgery had no influence on outcome in patients with idiopathic hearing loss. In contrast, in patients with barotrauma, time of surgery seems to have an influence on outcome. CONCLUSIONS: Tympanotomy and sealing of the round window membrane can be recommended in cases of acute hearing loss after failure of conservative treatment.

1,25(OH)2Vitamin D3 induces elevated expression of the cell cycle inhibitor p18 in a squamous cell carcinoma cell line of the head and neck.

BACKGROUND: 1Alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2) Vitamin D(3)] induces growth inhibition in squamous cell carcinoma (SCC) cell lines of the head and neck by arresting the cells in the G0/G1 phase of the cell cycle, probably due to an enhanced expression of p21, which could be demonstrated in other cell lines (JPPA, SCC9) before. In SCC25, a SCC cell line isolated from tongue, growth inhibition but no overexpression of p21 was detected. The retinoblastoma gene, as a direct target of G1 cyclin-CDK complexes, showed an obvious shift from the hyperphosphorylated to the hypophosphorylated form under 1,25(OH)(2)Vitamin D(3), which indicates that the growth inhibition takes place in the G0/G1 phase. To explore the possible pathway of growth inhibition in SCC25 we investigated other cell cycle inhibitors (p18, p19, p27). METHODS: Synchronized cells were treated with 1,25(OH)(2)Vitamin D(3) over 96 h. The cell cycle status and expression of cell cycle-regulating proteins was determined by fluorescence-activated cell sorting (FACS) and Western blotting. An overexpression of p18 in 1,25(OH)(2)Vitamin D(3) vs. ethanol-treated cells was determined until 30 h in SCC25. No influence was detectable on the expression of p27 and p19. CONCLUSION: One mechanism by which 1,25(OH)(2)Vitamin D(3) controls cell growth might be the upregulation of p21. As p21 was unsusceptible to 1,25(OH)(2)Vitamin D(3) in SCC25, other inhibiting proteins were necessary to be tested. The proven upregulation of p18 seems to be the responsible step for growth inhibition of 1,25(OH)(2)Vitamin D(3) in SCC25.

Nimesulide and indomethacin induce apoptosis in head and neck cancer cells.

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) are known to inhibit the enzyme cyclooxygenase (COX). There are two isoforms of the enzyme. Recent investigations indicate that both isoforms, COX-1 and COX-2, are involved in carcinogenesis. METHODS: We investigated the effects of nimesulide, a COX-2 selective and indomethacin, a non-selective NSAID on the head and neck squamous cell carcinoma (HNSCC) cell lines SCC-9 and SCC-25. Effects on cell numbers and apoptosis were assayed by cell counting, immunofluorescence and fluorescence activated cell sorting (FACS). COX expression was examined by Western blotting. RESULTS: The investigated cell lines express COX-1 and COX-2. Nimesulide and indomethacin induce apoptosis and cause a reduction of cell number. Incubation with NSAIDs upregulated COX-2 expression. CONCLUSION: The results of our study on HNSCC cells together with data from different studies showing anti-cancer activity of NSAIDs suggest that COX inhibitors could play a role in HNSCC treatment and prevention.

Vascular endothelial growth factor C and vascular endothelial growth factor receptor 3 expression in squamous cell carcinomas of the head and neck.

BACKGROUND AND METHODS: VEGF proteins and their receptors are involved in tumor vessel neoformation. The third VEGF receptor, VEGFR3 (flt-4) is important during both blood vessel development and lymphatic vessel formation. Because HNSCC preferentially metastasizes to regional lymph nodes, we investigated the expression of VEGFR3 and its ligand VEGF-C in head and neck squamous cell carcinomas by semiquantitative RT-PCR (4 HNSCC cells lines and 6 HNSCC specimens) and by immunohistochemistry (18 HNSCC specimens). VEGFR3 protein expression was confirmed by Western blotting in four HNSCC cell lines and six HNSCC specimens. RESULTS: Semiquantitative mRNA analysis showed VEGF-C mRNA expression in three (SCC9, SCC25, LFFR) of four HNSCC cell lines and all six HNSCC specimens. VEGFR3 mRNA was found in two HNSCC cell lines (JPPA and SCC25) and only weakly detected in the other two HNSCC cell lines (SCC9 and LFFR). High amounts of VEGFR3 mRNA were shown in all six patients' tumor specimens. VEGFR3 Western blot analysis yielded a distinct band at the predicted size of 210 kD in JPPA and SCC9 and hardly detectable bands in SCC25 and LFFR cell lines. All six HNSCC specimens displayed strong VEGFR3 protein bands. Immunohistochemistry in 18 HNSCC specimens assigned strong to mediate VEGF-C IR and minor VEGFR3 IR to tumor cells and strong VEGF-C and VEGFR3 IR to tumor surrounding vessels. In addition, intense VEGF-C immunostaining was observed on perivascular and mononuclear cells in the tumor surrounding stroma. Subtyping of VEGFR3+ microvascular tumor vessels revealed partially double immunolabeling with CD34 and flk-1, indicating a common origin of blood and lymphatic vessels. The expression of VEGF-C on tumor cells could be correlated with recurrences, and larger primary tumors had more VEGF-C-positive vessels. CONCLUSIONS: The broad expression of VEGF C and VEGFR3 in HNSCC suggests involvement in tumor lymph angiogenesis and vascular angiogenesis, promoting tumor growth and propagation of cancer cells. This implies that inhibitors of lymph angiogenesis could become effective therapeutic options similar to classical angiogenesis inhibitors.

Mitoxantrone and cisplatin in recurrent and/or metastatic salivary gland malignancies.

A phase II study was performed to assess the safety and efficacy of mitoxantrone and cisplatin in locally recurrent and/or metastatic carcinomas of the salivary glands. Between May 1997 and March 2001, a total of 14 patients were entered on this trial. All of them had previously undergone radical resection and 10 were subsequently treated with adjuvant radiation therapy with (n=3) or without (n=7) concomitant chemotherapy. Therapy according to the study protocol consisted of mitoxantrone given as i.v. bolus on day 1 at a dose of 12 mg/m2 and cisplatin given as 90-min infusion at a dose of 30 mg/m2 on days 1-3. We observed two partial responses (14.3%) and stabilization of disease in nine patients (64.3%); progression during therapy was noted in only three cases (21.4%). The median time to progression was 15 months (range 2-36) and the median survival time was 27 months (range 4-54). Myelosuppression was commonly observed. Leukocytopenia occurred in all patients, and was grade 3 or 4 in three (21%) and four (29%) patients. WHO grade 3 thrombocytopenia and anemia was seen in three (21%) and four (29%) patients, respectively. Non-hematologic toxicity was in general mild to moderate except for two cases (14%) of grade 3 nausea and vomiting; overall incidence rates were nausea and vomiting (n=14), stomatitis (n=6), diarrhea (n=3), alopecia (n=11), infection (n=7), increase of serum creatinine (n=3), and peripheral neuropathy (n=3). The combination of mitoxantrone and cisplatin seems to be an active and fairly well-tolerated regimen for the treatment of advanced salivary gland cancers. According to the observed high rate of abrogating progressive disease for a long duration, and the resulting promising progression-free and overall survival time, further investigation seems warranted.

Ethanol decreases negative cell-cycle-regulating proteins in a head and neck squamous cell carcinoma cell line.

Epidemiologic studies have provided evidence of an alcohol-associated increased risk of upper aerodigestive tract cancers. Recently we reported ethanol-induced proliferation in a squamous cell carcinoma of the head and neck (SCCHN) cell line, but the underlying mechanisms are unknown. In order to further clarify these findings, major G0/G1-regulating proteins were investigated in the present study. Synchronized cells of a SCCHN line (JP-PA) and a human immortalized keratinocyte line (HaCaT)-used as a control-were cultured with or without 10(-3) M ethanol for up to 96 h. At distinct time intervals the expression of cyclin D1 and the inhibitors p16, p18, p19 and p21 were determined by Western blot analyses. In both lines ethanol had no influence on the protein expression of cyclin D1. In contrast, distinct downregulations of p21, p18 and p19 were detectable at the protein level. The p16 protein was not expressed in the SCCHN line and was unchanged in the control line after the addition of ethanol. In these in vitro experiments the marked downregulation of important cell-cycle inhibitors may accelerate progression from the G1 to the S phase of the cell cycle. The relevance of our findings to in vivo conditions remains speculative, but the observed mechanisms of significantly reduced expression of cell-cycle inhibitor proteins may be involved in the carcinogenesis of head and neck malignancies.

Randomized multicenter phase II trial of oxaliplatin plus irinotecan versus raltitrexed as first-line treatment in advanced colorectal cancer.

PURPOSE: Irinotecan and oxaliplatin are two new agents with promising activity in advanced colorectal cancer. Based on preclinical and clinical evidence that both drugs act synergistically, a randomized phase II study was initiated to investigate the therapeutic potential and tolerance of this combination in the front-line setting. PATIENTS AND METHODS: Ninety-two patients with previously untreated, measurable disease were randomized to receive biweekly oxaliplatin 85 mg/m(2) plus irinotecan 175 mg/m(2) or raltitrexed 3 mg/m(2) given on day 1 every 3 weeks. Upon development of progressive disease, second-line treatment with the opposite arm was effected. RESULTS: Patients allocated to oxaliplatin/irinotecan had a significantly better radiologically confirmed response rate (43.5% v 19.6%; P =.0025) and longer progression-free survival (median, 7.1 v 5.0 months; P =.0033). Improvement in overall survival, however, did not reach the level of significance (median, 16.0 v 16.5 months; P =.3943). The response rate after cross-over was 33.3% (eight of 24) for assessable patients treated with oxaliplatin/irinotecan compared with 14.2% (three of 21) for those treated with second-line raltitrexed. Oxaliplatin/irinotecan caused more hematologic and gastrointestinal toxicities, necessitating dose reductions in 10 of the first 20 patients. After adjustment of the irinotecan starting dose from 175 to 150 mg/m(2), tolerance of treatment was acceptable; the most commonly encountered events (all grades) were neutropenia (81%), alopecia (65%), nausea/emesis (62%), peripheral sensory neuropathy (62%), and diarrhea (46%). CONCLUSION: Oxaliplatin/irinotecan seems beneficial as first-line therapy in advanced colorectal cancer, with an acceptable toxicity profile at the reduced irinotecan dose level. Its promising therapeutic potential is supported by the high response activity noted in the raltitrexed control arm after cross-over, which may also explain the lack of a difference in overall survival.