Salivary duct carcinoma: Updates in histology, cytology, molecular biology, and treatment.

Salivary duct carcinoma (SDC) is an aggressive subtype of primary salivary gland carcinoma, often with an advanced stage at presentation and high rates of metastasis and recurrence. It most commonly arises in the parotid gland of older men and microscopically resembles high-grade breast ductal carcinoma. While 50 years have lapsed since the first report of this entity, recent intensive studies have shed light on its biologic, genetic, and clinical characteristics. The diagnosis of SDC is aided by the immunohistochemical expression of androgen receptor (AR) coupled with its characteristic histomorphology. Fine-needle aspiration typically reveals cytologic features of high-grade carcinoma, and ancillary studies using cell block material can facilitate the specific diagnosis of SDC. In surgical specimens, certain histologic features are important prognostic factors, including nuclear pleomorphism, mitotic counts, vascular invasion, and the morphology at the invasion front. Several clinical studies have shown promising results using targeted therapy for AR and human epidermal growth factor receptor 2 (HER2), and the latest version of the National Comprehensive Cancer Network guidelines recommends the evaluation of AR and HER2 status before treatment. Recent molecular analyses have revealed multiple heterogeneous alterations in well-known oncogenes and tumor suppressor genes, including TP53, HRAS, PIK3CA, PTEN, and BRAF. Clinical trials of drugs targeting these genes may broaden the treatment options for SDC in the near future.

The Milan System at Memorial Sloan Kettering: Utility of the categorization system for in-house salivary gland fine-needle aspiration cytology at a comprehensive cancer center.

BACKGROUND: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) provides a standardized reporting system for salivary gland fine-needle aspiration (SGFNA). We review the clinical utility of the MSRSGC at a tertiary care cancer center by assessing the rates of malignancy (ROM) among different categories. METHODS: A retrospective search was performed to retrieve all SGFNA cases performed at our institution between 1/1/07 and 12/31/18. The initial primary diagnoses were recorded and cases were then assigned to appropriate MSRSGC categories. ROM was then calculated for all categories. RESULTS: A total of 976 cases were identified, and 373 with follow-up. The ROM was 19.7% (192/976) for all-comers and 51.3% (192/374) among cases with follow-up. Using MSRSGC, SGFNA showed a sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 65.6%, 87.4%, 100%, and 72.6%, respectively. ROM for MSRSGC categories I, II, III, IVa, IVb, V, and VI were 20.7%, 30.0%, 45.8%, 3.3%, 50.7%, 100%, and 100%, respectively. Utilizing MSRSGC resulted in a nondiagnostic rate of 14.4%. The nondiagnostic rate was lower when the procedure was performed by pathologists vs nonpathologists (12.9% vs 15.8%) but was comparable when rapid on site evaluation (ROSE) was performed (12.9% vs 11.6%). CONCLUSION: In our patient population, MSRSGC resulted in a perfect PPV and moderate NPV. Utilizing MSRSGC results in a higher nondiagnostic rate due to the inclusion of cases with benign elements or cyst contents only in this category. Performing ROSE is more important in attaining an adequate sample than the specialty of the person performing SGFNA.

Efficacy and toxicity of sorafenib in patients with adenoid cystic carcinoma of the head and neck: a case series of five patients.

INTRODUCTION: Adenoid cystic carcinoma (ACC) of the head and neck is a rare malignancy of the salivary glands that accounts for approximately 10% of salivary gland carcinoma. Despite aggressive local therapy, local recurrence and distant metastases occur frequently. Response rates (RR) to potential curative and palliative chemotherapy are limited, so new strategies are needed. CASE REPORTS: We describe five case reports of patients with unresectable locally advanced or metastatic ACC of the head and neck who have been treated with sorafenib, a multi-tyrosine kinase inhibitor (mTKI). RESULTS: In this case series, we found that three out of five patients treated with sorafenib survived, respectively, 16, 35 and 35 months. Two patients showed a partial response (PR) and one patient had a prolonged stable disease (SD) for almost three years. Grade 3 adverse events (AE) occur under sorafenib so adequate toxicity management is essential. This retrospective case series hints towards the possibility of clinical benefit for treating ACC patients with sorafenib. Efficacy of sorafenib should be studied in a prospective-randomized clinical trial which is a challenging task due to the rarity of the disease.

Serum Levels of Zinc, Copper and Ferritin in Patients with Salivary Gland Tumors

Background: Variation in serum levels of trace elements including zinc, copper and ferritin has been reported in cancer patients. The aim of this study was to evaluate these trace elements in the patients' sera with benign and malignant salivary gland tumors (SGTs) and compare them with normal individuals. Methods: In this cross-sectional study, 60 patients with SGTs including 16 pleomorphic adenoma and 44 malignant SGTs, as well as 28 healthy controls, were enrolled. Serum levels of zinc, copper and ferritin were determined by atomic absorption and ELISA methods. Data were analyzed using one way ANOVA, Chi-square, Kruskal-Wallis and Mann- Whitney tests. Results: The mean concentration of zinc, copper, ferritin was1.5± 2 ppm, 1.2± 0.5 ppm, and 96.7± 65.7 ng/ml in PA, 1.5± 1.4,1.3± 0.4, and 111.2± 112 in malignant SGTs, and1.1±0.3, 1.2± 0.23 and 124±135.8 in normal control groups. There was no statistically significant difference between the patients and control groups, and between benign and malignant SGTs (P>0.05). Conclusion: The serum levels of trace elements in SGTs were not different from normal individuals. The results might have been affected by some interventional factors. Therefore, designing cohort complementary studies might result in obtaining more accurate data.

Postoperative radiotherapy for T1/2N0M0 mucoepidermoid carcinoma positive for CRTC1/3-MAML2 fusions.

BACKGROUND: The National Comprehensive Cancer Network (NCCN) guidelines recommend considering postoperative radiotherapy (PORT) for completely resected T1/2N0M0 salivary mucoepidermoid carcinomas when they show tumor spillage, perineural invasion, or intermediate/high-grade histology. CRTC1/3-MAML2 fusions have been associated with a favorable clinical outcome. METHODS: Forty-seven T1/2N0M0 mucoepidermoid carcinoma cases positive for CRTC1/3-MAML2 fusions were completely resected and were not treated with PORT. RESULTS: Pathologically, none of the cases showed tumor spillage or perineural invasion. Cases with intermediate/high-grade histology numbered 9 (19%) to 26 (55%) with the currently used 3 different grading systems. During the follow-up (median 60 months), locoregional tumor recurrence occurred in 4 cases, which were treated with surgery alone. At the last follow-up (median 60 months; 7-160), all patients were alive with no evidence of disease. CONCLUSION: An excellent prognosis may be achieved without PORT in T1/2N0M0 mucoepidermoid carcinoma patients positive for CRTC1/3-MAML2 fusions when the tumors are completely resected without tumor spillage.

A multiplex preclinical model for adenoid cystic carcinoma of the salivary gland identifies regorafenib as a potential therapeutic drug.

Adenoid cystic carcinomas (ACC) are rare salivary gland cancers with a high incidence of metastases. In order to study this tumor type, a reliable model system exhibiting the molecular features of this tumor is critical, but none exists, thereby inhibiting in-vitro studies and the analysis of metastatic behavior. To address this deficiency, we have coupled an efficient method to establish tumor cell cultures, conditional reprogramming (CR), with a rapid, reproducible and robust in-vivo zebrafish model. We have established cell cultures from two individual ACC PDX tumors that maintain the characteristic MYB translocation. Additional mutations found in one ACC culture also seen in the PDX tumor. Finally, the CR/zebrafish model mirrors the PDX mouse model and identifies regorafenib as a potential therapeutic drug to treat this cancer type that mimic the drug sensitivity profile in PDX model, further confirming the unique advantages of multiplex system.

Silymarin and its active component silibinin act as novel therapeutic alternatives for salivary gland cancer by targeting the ERK1/2-Bim signaling cascade.

PURPOSE: Approximately 20% of all salivary gland cancer patients who are treated with current treatment modalities will ultimately develop metastases. Its most common form, mucoepidermoid carcinoma (MEC) is a highly aggressive tumor with an overall 5-year survival rate of ~30%. Until now, several chemotherapeutic drugs have been tested for the treatment of salivary gland tumors, but the results have been disappointing and the drugs often cause unwanted side effects. Therefore, several recent studies have focused on the potential of alternative and/or complementary therapeutic options, including the use of silymarin. METHODS: The effects of silymarin and its active component silibinin on salivary gland cancer-derived MC3 and HN22 cells and their underlying molecular mechanisms were examined using trypan blue exclusion, 4'-6-diamidino-2-phenylindole (DAPI) staining, Live/Dead, Annexin V/PI staining, mitochondrial membrane potential (ΔΨm) measurement, quantitative RT-PCR, soft agar colony formation and Western blotting analyses. RESULTS: We found that silymarin and silibinin dramatically increased the expression of the pro-apoptotic protein Bim in a concentration- and time-dependent manner and, concomitantly, induced apoptosis in MC3 and HN22 cells. We also found that ERK1/2 signaling inhibition successfully sensitized these cells to the apoptotic effects of silymarin and silibinin, which indicates that the ERK1/2 signaling pathway may act as an upstream regulator that modulates the silymarin/silibinin-induced Bim signaling pathway. CONCLUSIONS: Taken together, we conclude that ERK1/2 signaling pathway inhibition by silymarin and silibinin increases the expression of the pro-apoptotic Bcl-2 family member Bim which, subsequently, induces mitochondria-mediated apoptosis in salivary gland cancer-derived cells.

Postoperative iodine-125 interstitial brachytherapy for the early stages of minor salivary gland carcinomas of the lip and buccal mucosa with positive or close margins.

BACKGROUND: The purpose of this study was to present our preliminary exploration of safety and efficacy of postoperative low-dose-rate brachytherapy for the early clinical stages of minor salivary gland carcinomas of the lip and buccal mucosa. METHODS: Twenty-seven patients with the early stages of minor salivary gland carcinomas of the lip and buccal mucosa received postoperative 125 I seed interstitial brachytherapy from March 2005 to May 2015. Actuarial likelihood estimates for local control, overall survival, and disease-free survival were calculated by Kaplan-Meier method. RESULTS: The actuarial 3-year, 5-year, and 10-year local control rates were 94.7%, 82.9%, and 82.9%, respectively. The actuarial 3-year, 5-year, and 10-year overall survival rates were 93.3%, 93.3%, and 77.8%, respectively. No patient experienced toxicity above grade 2. CONCLUSION: Postoperative 125 I seed interstitial brachytherapy is an alternative to radical surgery for early stages of minor salivary gland carcinomas of the lip and buccal mucosa, which offers satisfactory cosmetic and functional outcomes. © 2017 Wiley Periodicals, Inc. Head Neck 39: 572-577, 2017.

A phase II study of sorafenib in recurrent and/or metastatic salivary gland carcinomas: Translational analyses and clinical impact.

BACKGROUND: Pre-clinical and clinical evidence suggests a rationale for the use of anti-angiogenic agents, including sorafenib, in recurrent and/or metastatic salivary gland carcinomas (RMSGCs). This study evaluates the activity of sorafenib in patients with RMSGCs and also investigates whether the activity of sorafenib could be related to its main tailored targets (i.e. BRAF, vascular endothelial growth factor receptor 2 [VEGFR2], platelet-derived growth factor receptor α [PDGFRα] and ß, RET, KIT). PATIENTS AND METHODS: Patients received sorafenib at 400 mg BID. The primary end-point was response rate (RR) including complete response or partial response (PR); secondary end-points included RR according to Choi criteria, disease control rate (DCR), overall survival (OS), and progression-free survival (PFS). RESULTS: Thirty-seven patients (19 adenoid cystic cancers, ACC) were enrolled. Six PRs were recorded. RR was 16% (95% confidence interval [CI]: 6-32; 11% in ACC and 22% in non-ACC). Choi criteria could be applied in 30 out of 37 cases with a RR of 50% (95% CI: 31-69%); DCR was 76% (95% CI: 59-88%). Incidence of ≥G3 adverse events was 29.7%. Median PFS and OS for the entire population were 5.9 months and 23.4 months, respectively. Median PFS and OS were 8.9 and 26.4 months for ACC versus 4.2 and 12.3 months for non-ACC patients. All the cases showed expression of PDGFRß in the stroma and VEGFR2 in endothelial cells; PDGFRα positivity was found in the stroma of four (27%) cases. All except for two cases showed no PDGFRß, VEGFR2 and PDGFRα expression in the tumour cells. KIT expression was restricted to ACC and a weak RET expression was limited to one adenocarcinoma, not otherwise specified (NOS). No BRAF mutation was found. No correlation was observed between the sorafenib activity and the expression of its markers although all six responders (two ACC, one adenocarcinoma, NOS, one salivary duct cancer [SDC], one high-grade mucoepidermoid [HG-MEC] and one poorly-differentiated cancer) are enriched in the stromal component showing a PDGFRß immunodecoration. In ACCs, immunohistochemistry revealed MYB protein expression in 15/16 cases (94%) and the MYB-NFIB fusion oncogene was observed in 9/14 (64%). CONCLUSIONS: Sorafenib is the first anti-angiogenic agent to demonstrate activity in RMSGC patients, particularly in some histotypes such as HG-MEC, SDC and adenocarcinoma, NOS. The PDGFRß-positive rich stromal component characterising these histotypes and the lack of correlation between the activity of sorafenib and its targets suggests anti-angiogenic effect as the prevalent mechanism of action of sorafenib in SGCs.

WIP1 stimulates migration and invasion of salivary adenoid cystic carcinoma by inducing MMP-9 and VEGF-C.

The wild-type p53 induced phosphatase 1 (WIP1) is an oncogene overexpressed in a variety of human cancers. Here, we demonstrated that WIP1 silencing reduced MMP-9 and VEGF-C expression as well as migration and invasion of salivary adenoid cystic carcinoma (ACC) cells. Overexpression of MMP-9 or VEGF-C restored migration and invasion in WIP1 knockdown cells, indicating that MMP-9 and VEGF-C are downstream targets of WIP1 signaling. Levels of cyclin D1 and c-Myc, targets of Wnt/ß-catenin pathway, were significantly decreased by WIP1 silencing. In addition, WIP1 expression was positively associated with metastasis and prognosis of ACC patients as well as with MMP-9 or VEGF-C in ACC tissues.

A case-cohort study of recurrent salivary adenoid cystic carcinoma after iodine 125 brachytherapy and resection treatment.

Recurrent adenoid cystic carcinoma (rAdCC) can be challenging to be treated with brachytherapy, although brachytherapy is safe and effective in treating head and neck cancers. Patients of adenoid cystic carcinoma (AdCC), who underwent resection and iodine 125 ((125)I) radioactive seed implantation, were recruited for this study. Clinical data, surgical details of resection and seed implantation, histologic characteristics, and prognosis were studied. There were 16 rAdCC cases among 140 cases of AdCC treated with brachytherapy and resection. The mean follow-up duration for the recurrent cases was 61 months. The 3-year local control rate of rAdCC was 51.6%, and the overall disease-specific survival rate was 49.4%. Eight patients showed distant metastasis (50%, 8/16). The histologic grades of 10 rAdCCs were upgraded (62.5%, 10/16).Two cases displayed sarcomatous transformation after brachytherapy (1.4%, 2/140). Although the overall local control rate and survival rate were relatively favorable, some rAdCCs with an aggressive phenotype appeared to respond poorly to (125)I seed implantation. Preventive adjuvant chemotherapy should be prescribed for these rAdCCs.

Inhibition of autophagy augments chemotherapy in human salivary adenoid cystic carcinoma.

Although cisplatin (DDP)-based adjuvant chemotherapy is widely used in the treatment of salivary adenoid cystic carcinoma (SACC), SACCs have developed resistance to cisplatin, resulting in chemotherapy failure. Autophagy serves as a critical adaptive response, which was increased in tumor cells in chemotherapy. However, the function of autophagy is not clear in SACC. In this study, apoptosis induced by DDP in SACC high metastatic cell line (ACC-M) was revealed using MTT assay, flow cytometry, and caspase-3 immunoblotting. The autophagy activation induced by DDP treatment was measured by transmission electron microscopy, green fluorescent protein-light chain 3 plasmid transfection LC3 immunoblotting and p62 immunoblotting. 3-methyladenine (3-MA) or small interference RNA targeting beclin 1 (beclin 1 siRNA) inhibited autophagy and significantly enhanced DDP-induced apoptosis. ACC-M xenografts in nude mice further verified the synergistic effect of DDP and 3-MA. In conclusion, autophagy activation was caused to protect cancer cells from DDP-induced apoptosis and autophagy inhibition could be a promising strategy for adjuvant chemotherapy in SACC.

Mechanisms of apple polyphenols-induced proliferation inhibiting and apoptosis in a metastatic oral adenoid cystic carcinoma cell line.

Adenoid cystic carcinoma (ACC) is characterized by intensive local invasion and high incidence of distant metastases. Conventional chemotherapy for ACC produces a poor result. We aimed to evaluate the effect of apple polyphenols (APs), a novel nutraceutical agent, on the proliferation and apoptosis levels in a metastatic oral ACC cell line. A metastatic ACC (ACC-M) cell line and control cells (MRC-5 cells derived from normal lung tissue) were treated with APs at different concentrations. MTT assay was used to determine the in vitro cytotoxicity. The cell cycle distribution and apoptosis levels were measured by flow cytometry. To evaluate the mechanism of APs, vascular endothelial growth factor receptor-2 (VEGFR-2) and caspase-3 messenger ribonucleic acid (mRNA) and protein levels were evaluated by reverse transcription-polymerase chain reaction and Western blots, respectively. After cells were cultured for 24 hours or 48 hours, the critical concentration of cytotoxicity of APs in MRC-5 cells was found to be 250 µg/mL. In contrast, in the concentration range of 100-250 µg/mL, the cytotoxicity of APs in ACC-M cells was time- and dose-dependent: ACC-M cell proliferation declined at 100 µg/mL when cultured for 48 hours, whereas growth was not inhibited at the concentrations of APs below 200 µg/mL when cultured for 24 hours. In selected time and dose patterns (ACC-M cells cultured at the concentrations of 150 and 250 µg/mL for 48 hours), the flow cytometry performance showed that apoptosis and necrosis occurred in APs-treated ACC-M cells. Also, in these patterns, VEGFR-2 mRNA and protein levels decreased whereas the levels of caspase-3 increased. In summary, APs could inhibit proliferation and induce apoptosis in ACC-M cells in vitro. These effects may be related to the downregulation of VEGFR-2 expression and the activation of caspase-3 expression.

125I brachytherapy alone for recurrent or locally advanced adenoid cystic carcinoma of the oral and maxillofacial region.

BACKGROUND AND PURPOSE: This retrospective study was to evaluate the local control and survival of (125)I brachytherapy for recurrent and/or locally advanced adenoid cystic carcinoma (ACC) of the oral and maxillofacial region. PATIENTS AND METHODS: A total of 38 patients with recurrent and/or locally advanced ACC of the oral and maxillofacial region received (125)I brachytherapy alone from 2001-2010. Twenty-nine were recurrent cases following previous surgery and radiation therapy. The other 9 cases involved primary tumors. Overall, 12 tumors were located in the major salivary glands, 12 in the minor salivary glands, and 14 in the paranasal region, the nasal cavity or the skull base. The prescribed dose was 100-160 Gy. RESULTS: Patients were followed for 12-122 months (median 51 months). The 2-, 5-, and 10-year local tumor control rates were 86.3, 59, and 31.5 %, respectively. The 2-, 5-, and 10-year overall survival rates were 92.1, 65 and 34.1 %, respectively. Tumors > 6 cm had significantly lower local control and survival rates. No severe complications were observed during follow-up. CONCLUSION: (125)I brachytherapy is a feasible and effective modality for the treatment of locally advanced unresectable or recurrent ACC.

Multiple osteolytic lesions of intraosseous adenoid cystic carcinoma in the mandible mimicking apical periodontitis.

AIM: Adenoid cystic carcinoma (ACC) is a relatively rare epithelial tumour of the salivary glands in the maxillofacial region. About 40-60% of the patients develop distant metastases, which have been documented most commonly in the lung but also in brain, bone, liver, thyroid, spleen and pancreatic gland. SUMMARY: A 55-year-old women with intraosseous ACC in the mandible mimicking apical periodontitis following curative resection and radiotherapy is presented. Three years later, multiple lung metastases were observed followed by chemotherapy. Five years after curative resection, the patient presented simultaneously with new expansive soft tissue in the pancreas and mammary gland as well as in the kidney found to be metastatic ACC. No case has been reported to date on the manifestation of distant metastases of intraosseous ACC in the breast and the kidney as described by these observations. Metastatic mammary gland ACC stained positive for epithelial growth factor receptor (EGFR) but was negative for HER-2/neu and Cyclooxygenase-2 (COX-2) expression.

Mucosa-associated lymphoid tissue lymphoma of the salivary glands: MR imaging findings including diffusion-weighted imaging.

PURPOSE: The purpose of this study was to describe MR findings including diffusion-weighted (DW) imaging findings in patients with mucosa-associated lymphoid tissue (MALT) lymphoma of the salivary glands. MATERIALS AND METHODS: Ten patients with histologically proven MALT lymphoma of the salivary glands were included. All patients underwent 1.5-T MR imaging, six of the ten underwent DW imaging, nine underwent CT, and eight (18)F-fluorodeoxyglucose (FDG) PET/CT. MR images were reviewed for numbers, locations, sizes, MR imaging characteristics, and apparent diffusion coefficients (ADCs). Calcium deposition and maximum standardized uptake values (SUVmax) were also assessed. RESULTS: Twenty-six tumors, ranging in number from 1 to 5 (mean, 2.6), were identified. Nine patients had tumors in the parotid glands and one in the submandibular glands. Tumors were found bilaterally in 7 patients and unilaterally in three. Tumors ranged in size from 0.6 to 5.5cm (mean, 1.8cm). Ten (38%) tumors had intratumoral cystic formations and 8 (31%) had ill-demarcated margins. DW images showed hyperintensity with extremely low ADCs (range, 0.48-0.82 [×10(-3)mm(2)/s]; mean, 0.64) for solid components of all 19 tumors in the 6 examined patients. Calcium deposition was found in one (4%) tumor on CT. SUVmax variously ranged from 1.3 to 17.7 (mean, 6.3). CONCLUSION: Salivary gland MALT lymphomas were often found bilaterally and were occasionally accompanied by intratumoral cystic formations and ill-demarcated margins. DW imaging may play a supplementary role in the diagnosis of lymphoma, because it showed restricted water molecule diffusion, whereas PET/CT showed indeterminate findings.

Subchronic toxicity and genotoxicity of diiodomethyl-p-tolylsulfone (DIMPTS) in laboratory animals.

These studies were conducted to determine subchronic toxicity and genotoxicity of the biocide diiodomethyl-p-tolysulfone (DIMPTS) in rats and dogs. Male and female Sprague-Dawley rats and Beagle dogs were administered DIMPTS for 90-days via the diet at 0, 5, 20, and 80 mg/kg/day to rats and via capsules at 0, 2, 10, and 60 mg/kg/day to dogs. In rats, the only treatment-related finding was squamous metaplasia of the salivary gland duct in the 80 mg/kg/day group. In dogs, female body weights in the high-dose group were significantly lower than controls. Altered clinical pathology parameters were considered secondary to inflammatory changes observed in some of the dogs. Treatment-related alterations were found in the thyroid glands, salivary glands, GI-tract in the mid- and/or high-dose groups. DIMPTS was negative in the four in vitro and one in vivo genotoxicity assays. The toxicological effects noted in the two mammalian species are consistent with the principal toxic effects of iodine, and are proposed to arise from release of iodide from the DIMPTS molecule with toxic sequelae.

Adjuvant chemoradiotherapy for locoregionally advanced and high-risk salivary gland malignancies.

BACKGROUND: To report the outcomes of patients with locoregionally advanced and high- risk salivary gland malignancies treated with surgery followed by adjuvant chemoradiotherapy. METHODS: From 09/1991 - 06/2007, 24 high-risk salivary gland cancer patients were treated with surgery, followed by adjuvant chemoradiotherapy for high-risk pathologic features including, perineural involvement, nodal involvement, positive margins, or T3/T4 tumors. Chemoradiotherapy was delivered for 4-6 alternating week cycles: the most common regimen, TFHX, consisted of 5 days paclitaxel (100 mg/m² on d1), infusional 5-fluorouracil (600 mg/m²/d × 5d), hydroxyurea (500 mg PO BID), and 1.5 Gy twice daily irradiation followed by a 9-day break without treatment. RESULTS: Median follow-up was 42 months. The parotid gland was more frequently involved (n = 17) than minor (n = 4) or submandibular (n = 3) glands. The median radiation dose was 65 Gy (range 55-68 Gy). Acute treatment related toxicity included 46% grade 3 mucositis and 33% grade 3 hematologic toxicity. Six patients required feeding tubes during treatment. One patient progressed locally, 8 patients progressed distantly, and none progressed regionally. Five-year locoregional progression free survival was 96%. The 3 and 5 year overall survival was 79% and 59%, respectively. Long-term complications included persistent xerostomia (n = 5), esophageal stricture requiring dilatation (n = 1), and tempromandibular joint syndrome (n = 1). CONCLUSIONS: Surgical resection followed by adjuvant chemoradiotherapy results in promising locoregional control for high-risk salivary malignancy patients.

Mammalian target of rapamycin pathway promotes tumor-induced angiogenesis in adenoid cystic carcinoma: its suppression by isoliquiritigenin through dual activation of c-Jun NH2-terminal kinase and inhibition of extracellular signal-regulated kinase.

Tumor-induced angiogenesis is essential for invasive growth and hematogenous metastasis of adenoid cystic carcinoma (ACC), a highly aggressive neoplasm mostly occurring in salivary glands. Previous studies have indicated that strategies directed against angiogenesis will help develop new therapeutic agents for ACC. The Chinese folk medicine licorice has been used for years as a natural remedy for angiogenesis-related diseases. In this study, we examined the effects of isoliquiritigenin (ISL), a flavonoid isolated from licorice, on the growth and viability of ACC cells and observed a concentration-dependent (0-20 microM) inhibition of cell growth without cell death at 24 h. In a further mimic coculture study, ISL effectively suppressed the ability of ACC cells to induce in vitro proliferation, migration, and tube formation of human endothelial hybridoma (EAhy926) cells as well as ex vivo and in vivo angiogenesis, whereas it exerted no effect on EAhy926 cells when added directly or in the presence of vascular endothelial growth factor (VEGF). The data also showed that the specific suppression of tumor angiogenesis by ISL was caused by down-regulation of mammalian target of rapamycin (mTOR) pathway-dependent VEGF production by ACC cells, correlating with concurrent activation of c-Jun NH(2)-terminal kinase (JNK) and inhibition of extracellular signal-regulated kinase (ERK). Most importantly, ISL also significantly decreased microvessel density within xenograft tumors, associating with the reduction of VEGF production and suppression of the mTOR pathway coregulated by JNK and ERK, as revealed by immunohistochemical studies and clustering analysis. Taken together, our results highlight the fact that ISL is a novel inhibitor of tumor angiogenesis and possesses great therapeutic potential for ACC.

(-)-Epigallocatechin-3-gallate inhibits invasion and migration of salivary gland adenocarcinoma cells.

(-)-Epigallocatechin-3-gallate (EGCG) has inhibitory effect on a variety of cancers by inducing apoptosis and cell cycle arrest or inhibiting angiogenesis and metastasis. EGCG has been found to induce apoptosis in salivary gland carcinoma cells, however, it is not known whether EGCG affects invasion and migration. Thus, this study was performed to clarify whether EGCG affects invasion and migration of salivary gland tumors. Matrigel invasion assay, wound scratch assay and migration assay using commercial kit were performed. beta1 integrin expression and activation of its downstream molecules such as focal adhesion kinase (FAK), AKT and extracellular signal-regulated kinase (ERK) were examined by Western blot. Enzymatic activity of matrix metalloprotease (MMP)-2 and MMP-9 was examined by gelatin zymography. EGCG inhibited effectively invasion and migration of SGT cells in a dose-dependent manner. EGCG also inhibited the activation of beta1 integrin-downstream molecules such as FAK, AKT and ERK as well as the expression of beta1 integrin itself. Moreover, MMP-2 and MMP-9 expression and their enzymatic activity were reduced by EGCG in a dose-dependent manner. These results indicate that EGCG may effectively suppress salivary gland tumors by inhibiting metastasis through beta1 integrin-mediated signaling.