A phase 2 study of MK-2206 in patients with incurable adenoid cystic carcinoma (Alliance A091104).

BACKGROUND: Recurrent/metastatic adenoid cystic carcinoma (ACC) is a rare, incurable disease. MYB is a putative oncogenic driver in ACC that is often overexpressed through an MYB-NFIB rearrangement. The authors hypothesized that AKT inhibition with the allosteric inhibitor MK-2206 could decrease MYB expression and induce tumor regression in patients with incurable ACC (ClinicalTrials.gov identifier NCT01604772). METHODS: Patients with progressive, incurable ACC were enrolled and received MK-2206 150 mg weekly; escalation to 200 mg was allowed. The primary end point was confirmed response. Secondary end points were progression-free survival, overall survival, and safety. An exploratory analysis evaluating the effect of MK-2206 on MYB expression was conducted in a subset of patients. RESULTS: Sixteen patients were enrolled, and 14 were evaluable for efficacy. No confirmed responses were observed. Thirteen patients had stable disease, and one had disease progression as their best response. The median progression-free survival was 9.7 months (95% CI, 3.8-11.8 months), and the median overall survival was 18.0 months (95% CI, 11.8-29.9 months). Nine of 16 patients (56%) had at least one grade 3 treatment-related adverse event, and the most common were rash (38%), fatigue (19%), decreased lymphocyte count (13%), and hyperglycemia (13%). Twelve of 14 tumors (86%) had detectable MYB expression by immunohistochemistry, and seven of 14 tumors (50%) had an MYB-NFIB gene rearrangement. Serial biopsies revealed decreased MYB levels with MK-2206 in four of five patients. CONCLUSIONS: MK-2206 failed to induce clinical responses in patients with incurable ACC. AKT inhibition may diminish MYB protein levels, although the effect was highly variable among patients. Novel approaches to target MYB in ACC are needed.

Anti-NOTCH1 therapy with OMP-52 M51 inhibits salivary adenoid cystic carcinoma by depressing epithelial-mesenchymal transition (EMT) process and inducing ferroptosis.

Salivary adenoid cystic carcinoma (ACC) is a common type of salivary gland cancer, and the mechanisms underlying its progression still remain poorly understood without efficient therapies. NOTCH1, an evolutionally conserved cell-cell signaling pathway, is involved in the progression of ACC. In our study, we attempted to explore whether NOTCH1 suppression using the monoclonal anti-NOTCH1 antibody OMP-52 M51 could be of potential for ACC treatment. Here, we identified NOTCH1 elevation in human ACC tissues compared with the matched normal samples. Patients with metastasis expressed much higher NOTCH1. We then found that OMP-52 M51 markedly reduced the expression of NOTCH1 and its intracellular active form NICD1 (NOTCH1 intracellular domain). Importantly, OMP-52 M51 markedly reduced the proliferation, migration and invasion of ACC cells. RNA-Seq and in vitro studies further showed that OMP-52 M51 significantly induced ferroptosis in ACC cells, indicated by the increased cellular malondialdehyde (MDA), iron contents and lipid ROS production, and decreased glutathione (GSH) levels. Further, remarkable glutathione peroxidase 4 (GPX4) reduction was detected in ACC cells with OMP-52 M51 treatment. However, promoting NOTCH1 expression markedly abolished the function of OMP-52 M51 to induce ferroptosis. Intriguingly, low-dose OMP-52 M51 strongly facilitated the capacity of ferroptosis inducer erastin to trigger ferroptotic cell death, revealing that OMP-52 M51 could improve the sensitivity of ACC cells to ferroptosis. In vivo, OMP-52 M51 administration suppressed tumor growth and induced ferroptosis in the constructed ACC xenograft mouse model. Collectively, our findings demonstrated that NOTCH1 inhibition by OMP-52 M51 represses the proliferation and epithelial-mesenchymal transition (EMT) in ACCs, and promotes ferroptosis, revealing the potential therapeutical application of OMP-52 M51 in ACC.

Efficacy of Cetuximab Combined with Paclitaxel in Patients with Recurrent Salivary Gland Carcinoma: A Retrospective Observational Study.

INTRODUCTION: Due to the rarity and various histological types, a standard chemotherapy regimen for recurrent or metastatic salivary gland carcinoma (SGC) has not been established. Molecular-targeted therapy is a novel cancer therapy based on the expression of target molecules. However, few molecular-targeted therapy types have shown satisfactory efficacy for patients with SGC. Our study described promising results of epidermal growth factor receptor (EGFR)-targeting therapy with paclitaxel in patients with SGC. METHODS: The medical records of patients with recurrent SGC treated with weekly cetuximab combined with paclitaxel (Cmab-PTX) between December 2017 and December 2022 at our institutions were retrospectively analyzed. RESULTS: Seven patients with SGC received Cmab-PTX therapy. The median age was 76 years. All patients were high-grade histological types, and EGFR expression was positive in all examined patients. Cmab-PTX was administered for a median period of 20 months (range of 2-36 months). The overall responses were three with complete response, two with partial response, one with stable disease (>24 weeks), and one with progressive disease. The objective response and disease control rates were 71.4% and 85.7%, respectively. Progression-free survival ranged between 2 and 36 months (median 12 months), whereas overall survival ranged between 4 and 111 months (median 36 months). One patient experienced a grade 4 adverse event (neutropenia), which was conservatively manageable. CONCLUSION: Although the treatment sensitivity of SGC with high-grade histological types is usually poor, Cmab-PTX could be a promising treatment regimen for recurrent SGC. Due to the rarity and various histological types, a standard chemotherapy regimen for recurrent or metastatic salivary gland carcinoma (SGC) has not been established. Molecular-targeted therapy is a novel cancer therapy based on the expression of target molecules. However, few molecular-targeted therapy types have shown satisfactory efficacy in patients with SGC. Our study described promising results of cetuximab (Cmab), epidermal growth factor receptor (EGFR)-targeting therapy with paclitaxel (PTX) in patients with SGC. Seven patients with SGC received Cmab-PTX therapy. The median age was 76 years. All patients were high-grade histological types, and EGFR expression was positive in all examined patients. Cmab-PTX was administered for a median period of 20 months. The overall responses were three with complete response, two with partial response, one with stable disease (>24 weeks), and one with progressive disease. The objective response rate was 71.4%. Progression-free survival ranged between 2 and 36 months (median 12 months), whereas overall survival ranged between 4 and 111 months (median 36 months). One patient experienced a grade 4 adverse event (neutropenia), which was conservatively manageable. Our study revealed a preferable objective response rate of Cmab-PTX for patients with high-grade SGC. Although the treatment sensitivity of SGC with high-grade histological types is usually poor, Cmab-PTX could be a promising treatment regimen for recurrent SGC.

Systemic therapies for salivary gland carcinomas: an overview of published clinical trials.

BACKGROUND: There is no consensus about effective systemic therapy for salivary gland carcinomas (sgcs). Our aim was summarized the clinical trials assessing the systemic therapies (ST) on sgcs. MATERIAL AND METHODS: Electronic searches were carried out through MEDLINE/pubmed, EMBASE, Scopus, Web of Science, and the Cochrane Library databases, and gray literature. RESULTS: Seventeen different drugs were evaluated, and the most frequent histological subtype was adenoid cystic carcinoma (n=195, 45.5%). Stable disease, observed in 11 ST, achieved the highest rate in adenoid cystic carcinoma treated with sunitinib. The highest complete (11.1%) and partial response (30.5%) rates were seen in androgen receptor-positive tumors treated with leuprorelin acetate. CONCLUSIONS: Despite all the advances in this field, there is yet no effective evidence-based regimen of ST, with all the clinical trials identified showing low rates of complete and partial responses. Further, translational studies are urgently required to characterize molecular targets and effective ST.

Systemic and Targeted Therapies in Adenoid Cystic Carcinoma.

OPINION STATEMENT: Adenoid cystic carcinoma (ACC) is an often-indolent type of salivary gland cancer (SGC). A subset of patients develops progression or aggressive disease warranting systemic therapy in the recurrent/metastatic (R/M) setting. We recommend genomic testing for all patients with R/M disease to aid with prognostication and eligibility for potential experimental therapies. Here, we review the currently available treatment options (cytotoxic chemotherapies and vascular endothelial growth factor receptor (VEGFR)-targeting tyrosine kinase inhibitors (TKIs)). Based on limited data, we nominate regimens which may have more favorable efficacy profiles. Among the cytotoxic chemotherapies, several regimens are acceptable when incorporating a platinum agent. Among the VEGFR-targeting TKIs, lenvatinib and axitinib are the preferred options. Larger, randomized studies prioritizing combinations with mechanistic synergism are needed. Predictive biomarkers are critical, as there is currently little evidence to guide sequencing of available options for individual patients. Immunotherapy is an available option, but has been associated with only modest benefit in ACC. We go on to review other therapies that have been studied and nominate those with promise based on early clinical data.

Role of Histone Deacetylases in the Pathogenesis of Salivary Gland Tumors and Therapeutic Targeting Options.

Salivary gland tumors (SGTs) comprise a rare and heterogenous category of benign/malignant neoplasms with progressively increasing knowledge of the molecular mechanisms underpinning their pathogenesis, poor prognosis, and therapeutic treatment efficacy. Emerging data are pointing toward an interplay of genetic and epigenetic factors contributing to their heterogeneity and diverse clinical phenotypes. Post-translational histone modifications such as histone acetylation/deacetylation have been shown to actively participate in the pathobiology of SGTs, further suggesting that histone deacetylating factors (HDACs), selective or pan-HDAC inhibitors (HDACis), might present effective treatment options for these neoplasms. Herein, we describe the molecular and epigenetic mechanisms underlying the pathology of the different types of SGTs, focusing on histone acetylation/deacetylation effects on gene expression as well as the progress of HDACis in SGT therapy and the current status of relevant clinical trials.

Exposure-toxicity relationship of cabozantinib in patients with renal cell cancer and salivary gland cancer.

Cabozantinib is registered in fixed 60 mg dose. However, 46% to 62% of patients in the registration studies needed a dose reduction due to toxicity. Improved clinical efficacy has been observed in renal cell carcinoma patients (RCC) with a cabozantinib exposure greater than 750 µg/L. In our study we explored the cabozantinib exposure in patients with different tumour types. We included RCC patients from routine care and salivary gland carcinoma (SGC) patients from a phase II study with ≥1 measured Cmin at steady-state. The geometric mean (GM) Cmin at the starting dose, at 40 mg and at best tolerated dose (BTD) were compared between both tumour types. Forty-seven patients were included. All SGC patients (n = 22) started with 60 mg, while 52% of RCC patients started with 40 mg. GM Cmin at the start dose was 1456 µg/L (95% CI: 1185-1789) vs 682 µg/L (95% CI: 572-812) (P < .001) for SGC and RCC patients, respectively. When dose-normalised to 40 mg, SGC patients had a significantly higher cabozantinib exposure compared to RCC patients (Cmin 971 µg/L [95% CI: 790-1193] vs 669 µg/L [95% CI: 568-788]) (P = .005). Dose reductions due to toxicity were needed in 91% and 60% of SGC and RCC patients, respectively. Median BTD was between 20 to 30 mg for SGC and 40 mg for RCC patients. GM Cmin at BTD were comparable between the SGC and the RCC group, 694 µg/L (95% CI: 584-824) vs 583 µg/L (95% CI: 496-671) (P = .1). The observed cabozantinib exposure at BTD of approximately 600 µg/L is below the previously proposed target. Surprisingly, a comparable exposure at BTD was reached at different dosages of cabozantinib for SGC patients compared to RCC patients Further research is warranted to identify the optimal exposure and starting dose to balance efficacy and toxicity.

Case report: ado-trastuzumab as second-line treatment in HER2 positive salivary duct carcinoma.

The objective of this report is to present the use and efficacy of ado-trastuzumab as an advanced line of therapy in salivary duct carcinoma (SDC) patient. An 84-year-old gentleman diagnosed with metastatic salivary duct tumor harboring overexpressed human epidermal growth factor receptor-2 has gone through resection surgery. The first line of treatment included initial doublet chemotherapy combined with trastuzumab, which was continued later as maintenance. PET-CT follow-up for 4 years has demonstrated no evidence of disease. However, upon recurrence, use of Ado-trastuzumab emtansine was prompted as second-line of treatment. This targeted patient-tailored therapy has accomplished a complete response. The effectiveness of ado-trastuzumab emtansine was notable within a short time period of two treatment cycles leading to full recovery. Specific agents aimed at altered oncogenes should be considered as a potential drug of choice in neoadjuvant HER2 positive SDC.

Systemic therapy for salivary gland malignancy: current status and future perspectives.

Salivary gland malignancies are rare neoplasms that have a broad histological spectrum and a variety of biologic behaviors. Salivary gland malignancies are known as chemo-resistant tumors, which render optimal treatment challenging. This review summarizes the role of systemic therapy for salivary gland malignancies. To date, the advantage of adding concurrent chemotherapy has remained undefined for both postoperative and inoperable locally advanced salivary gland malignancy patients undergoing radiotherapy. For recurrent/metastatic disease, local and/or systemic treatment options should be discussed in a multidisciplinary setting with consideration to both patient needs and tumor factors. For symptomatic patients or those who may compromise organ function, palliative systemic therapy can be a reasonable option based on the results of phase II studies. Platinum combination regimens as first-line therapy have been widely accepted. Personalized therapies have become established options, particularly for androgen receptor-positive, HER2-positive and NTRK fusion-positive salivary gland malignancies (i.e. androgen receptor and HER2 in salivary duct carcinoma and NTRK3 in secretory carcinoma). For patients with adenoid cystic carcinoma, multi-targeted tyrosine kinase inhibitors have also been developed. Anti-PD1 checkpoint inhibitors have shown limited activity to date. Investigation of active systemic treatments for salivary gland malignancy remains a significant unmet need. Future directions might include a more comprehensive genomic screening approach (usually next-generation sequencing-based) and combination strategies using immune checkpoint inhibitors. These are rare malignancies that require ongoing effort in the conduct of high-quality clinical trials.

[Novel therapeutic approaches for salivary gland carcinomas]. / Neue Therapieansätze für Speicheldrüsenmalignome.

Novel therapeutic options for the treatment of salivary gland malignancies have emerged due to the improvement and distribution of molecular pathological testing methods and the availability of targeted therapies. Since they are less toxic, these new agents are a valuable alternative to conventional cytotoxic chemotherapy. On the one hand, there are new entity-specific therapies such as NTRK inhibitor therapy for secretory carcinomas and axitinib therapy for adenoid cystic carcinomas. Moreover, cross-entity therapeutics such as antiandrogenic therapy, HER2 inhibition, and PI3K inhibition are also coming to the fore. For metastatic/recurrent salivary gland carcinomas that cannot be treated with targeted therapy, platinum-based chemotherapies continue to be therapy of choice.

Clinical Activity of Selitrectinib in a Patient With Mammary Analogue Secretory Carcinoma of the Parotid Gland With Secondary Resistance to Entrectinib.

NTRK gene fusions are found in <1% of all cancers but are uniformly present in mammary analog secretory carcinomas (MASC) of the salivary glands. Two selective histology-agnostic tropomyosin receptor kinase (TRK) inhibitors are currently approved for malignancies with these oncogenic fusions. Resistance to TRK inhibition has been recognized, and the mediating mechanisms are presently being studied. This report describes a patient diagnosed with an MASC of the parotid gland who after undergoing multiple lines of treatment was found to have an ETV6-NTRK3 fusion and initiated TRK-targeted therapy using entrectinib. Upon disease progression, we performed tumor genetic sequencing that showed a secondary resistance mutation. The patient subsequently responded to selitrectinib, a next-generation TRK inhibitor.

Prediction of clinical benefit from androgen deprivation therapy in salivary duct carcinoma patients.

Androgen deprivation therapy (ADT) is first-line palliative treatment in androgen receptor-positive (AR+) salivary duct carcinoma (SDC), and response rates are 17.6-50.0%. We investigated potential primary ADT resistance mechanisms for their predictive value of clinical benefit from ADT in a cohort of recurrent/metastatic SDC patients receiving palliative ADT (n = 30). We examined mRNA expression of androgen receptor (AR), AR splice variant-7, intratumoral androgen synthesis enzyme-encoding genes AKR1C3, CYP17A1, SRD5A1 and SRD5A2, AR protein expression, ERBB2 (HER2) gene amplification and DNA mutations in driver genes. Furthermore, functional AR pathway activity was determined using a previously reported Bayesian model which infers pathway activity from AR target gene expression levels. SRD5A1 expression levels and AR pathway activity scores were significantly higher in patients with clinical benefit from ADT compared to those without benefit. Survival analysis showed a trend toward a longer median progression-free survival for patients with high SRD5A1 expression levels and high AR pathway activity scores. The AR pathway activity analysis, and not SRD5A1 expression, also showed a trend toward better disease-free survival in an independent cohort of locally advanced SDC patients receiving adjuvant ADT (n = 14) after surgical tumor resection, and in most cases a neck dissection (13/14 patients) and postoperative radiotherapy (13/14 patients). In conclusion, we are the first to describe that AR pathway activity may predict clinical benefit from ADT in SDC patients, but validation in a prospective study is needed.

Tipifarnib in recurrent, metastatic HRAS-mutant salivary gland cancer.

BACKGROUND: To the authors' knowledge, there are no approved therapies for recurrent, metastatic (R/M) salivary gland carcinoma (SGC), but molecularly targeted therapies warrant ongoing investigation. In the current study, the authors have reported on the efficacy of tipifarnib in patients with aggressive HRAS-mutant, R/M SGC. METHODS: The current prospective, nonrandomized, multicenter, international cohort study involved 8 centers and was conducted from May 2015 to June 2019. The median follow-up was 22 months (range, 6-55 months). Subjects with HRAS-mutant R/M SGC (any histology) and disease progression within the last 6 months were enrolled. Tipifarnib was dosed orally twice daily. The authors determined the objective response rate using Response Evaluation Criteria in Solid Tumors (version 1.1), duration of response, and molecular predictors of response. RESULTS: A total of 13 patients with R/M SGC were enrolled; all had received prior systemic therapy (1-3 regimens). One objective response was observed; an additional 7 of 12 evaluable patients (58%) had stable disease as their best response with a median duration of 9 months (range, 3-14 months). Five of 7 patients had >10% tumor regression and 6 of 7 had stable disease lasting >6 months. Q61R was the most frequent activating HRAS mutation noted (7 of 13 patients; 54%), but gene variant and allele frequency did not correlate with outcomes. The median progression-free survival was 7 months (95% confidence interval, 5.9-10.1 months), and the median overall survival was 18 months (95% confidence interval, 9.6-22.4 months) with approximately 58.6% of patients alive at 1 year. Survival was similar regardless of HRAS mutant variant or co-occurring PIK3CA alterations. No participant discontinued treatment because of toxicity. CONCLUSIONS: Tipifarnib resulted in modest clinical activity with a promising disease control rate among patients with HRAS-mutant, R/M SGC who developed disease progression within the last 6 months.

Patients with adenoid cystic carcinomas of the salivary glands treated with lenvatinib: Activity and quality of life.

BACKGROUND: The treatment of patients with recurrent and/or metastatic (R/M) salivary gland adenoid cystic carcinoma (ACC) remains an unmet need. METHODS: Patients with R/M disease with a history of clinical or symptomatic disease progression within 6 months and a maximum of 1 previous line of chemotherapy or a multiple kinase inhibitor received oral lenvatinib at a dose of 24 mg/day. The primary endpoint was the objective response rate; secondary endpoints included quality of life (QOL) (according to the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 Items [EORTC QLQ-C30] and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core Module Head and Neck Module [EORTC QLQ-H&N35]), progression-free survival and overall survival, duration of response, and toxicities. RESULTS: Twenty-eight patients with R/M ACC were enrolled. Among 26 evaluable patients, 3 partial responses (11.5%) were reported. Target lesion reductions between 23% to 28% were observed in 4 of 20 patients with stable disease. Treatment-related adverse events were frequent (all grades, 96%; grade≥3 in 50% of cases according to version 4.03 of the National Cancer Institute Common Terminology Criteria for Adverse Events). The dose of lenvatinib was reduced in 24 patients, whereas in 21 patients the dose was reduced within the first 12 weeks and 4 patients maintained the full dose throughout treatment. The QOL deteriorated between baseline and 6 months with regard to Fatigue and Dry Mouth. There was no evidence of changes in Swallowing and Physical Functioning. At a median follow-up of 29 months, 2 patients remained on treatment, 10 patients were off protocol for disease progression and were alive with disease, and 14 patients had died of disease progression. The median overall survival, progression-free survival, and duration of response were 27 months, 9.1 months, and 3.1 months, respectively. CONCLUSIONS: Lenvatinib appears to have modest activity in ACC. Toxicities are common but manageable and QOL was found to deteriorate in some domains.

The Benefits of Adjuvant Trastuzumab for HER-2-Positive Salivary Gland Cancers.

BACKGROUND: Although high-grade salivary gland cancers (SGCs) often express androgen receptor (AR) and/or HER-2/neu, therapeutically targeting these receptors in SGC remains investigational. We investigated the prevalence of receptor expression and the benefit of adjuvant HER-2 directed therapy in the high-risk postoperative setting and explored the clinical utility of sequentially targeting these receptors in the setting of advanced disease. MATERIALS AND METHODS: We clinically annotated 95 patients with SGC (excluding adenoid cystic carcinoma) treated at our institution from 2002 to 2019 and recorded AR, HER-2/neu status, and tumor genomic profiling results when available. Clinicopathologic information was then integrated with outcomes. RESULTS: Of 95 patients, most had high-risk histologies, with salivary duct carcinoma (SDC) as the most frequent diagnosis (43, 45%). Thirty-five (37%) experienced recurrence (51% SDC). HER-2/neu was positive (1-3+) by immunostaining in 34 of 52 (65%) evaluable cases. There was no difference in survival based on HER-2/neu or AR expression. Nine of 17 (53%) patients with HER-2+ SDC received adjuvant chemoradiation with trastuzumab. Median disease-free survival (DFS) and overall survival (OS) were longer among patients with HER-2/neu 3+ staining tumors who received adjuvant trastuzumab versus those who did not (DFS, 117 vs. 9 months; p = .02; OS, 74 vs. 43 months; p = .02), with no difference among other HER-2/neu subgroups (0-2+). Two of nine (22%) patients treated with adjuvant trastuzumab demonstrated recurrence, both with low HER-2/neu staining intensity (1+). Longer time to recurrence (hazard ratio, 0.94; p = .01) predicted improved outcomes. Both androgen deprivation and HER-2-directed therapies had clinical benefit beyond the first-line metastatic setting, with partial response observed beyond second-line use. CONCLUSION: Although prospective data are lacking, the use of adjuvant trastuzumab in high-risk patients with SGC appears beneficial, particularly among patients with tumors exhibiting HER-2/neu 3+ immunostaining. IMPLICATIONS FOR PRACTICE: Results of this study showed an improved disease-free and overall survival in patients treated with adjuvant trastuzumab for high-risk salivary gland cancers with strong HER-2/neu staining intensity. Following recurrence or metastatic spread, sequential HER-2, and androgen-directed therapies may benefit certain patients with salivary gland cancer.

Targeted therapy for advanced salivary gland carcinoma based on molecular profiling: results from MyPathway, a phase IIa multiple basket study.

BACKGROUND: Systemic therapy options for salivary cancers are limited. MyPathway (NCT02091141), a phase IIa study, evaluates targeted therapies in non-indicated tumor types with actionable molecular alterations. Here, we present the efficacy and safety results for a subgroup of MyPathway patients with advanced salivary gland cancer (SGC) matched to targeted therapies based on tumor molecular characteristics. PATIENTS AND METHODS: MyPathway is an ongoing, multiple basket, open-label, non-randomized, multi-center study. Patients with advanced SGC received pertuzumab + trastuzumab (HER2 alteration), vismodegib (PTCH-1/SMO mutation), vemurafenib (BRAF V600 mutation), or atezolizumab [high tumor mutational burden (TMB)]. The primary endpoint is the objective response rate (ORR). RESULTS: As of January 15, 2018, 19 patients with SGC were enrolled and treated in MyPathway (15 with HER2 amplification and/or overexpression and one each with a HER2 mutation without amplification or overexpression, PTCH-1 mutation, BRAF mutation, and high TMB). In the 15 patients with HER2 amplification/overexpression (with or without mutations) who were treated with pertuzumab + trastuzumab, 9 had an objective response (1 complete response, 8 partial responses) for an ORR of 60% (9.2 months median response duration). The clinical benefit rate (defined by patients with objective responses or stable disease >4 months) was 67% (10/15), median progression-free survival (PFS) was 8.6 months, and median overall survival was 20.4 months. Stable disease was observed in the patient with a HER2 mutation (pertuzumab + trastuzumab, n = 1/1, PFS 11.0 months), and partial responses in patients with the PTCH-1 mutation (vismodegib, n = 1/1, PFS 14.3 months), BRAF mutation (vemurafenib, n = 1/1, PFS 18.5 months), and high TMB (atezolizumab, n = 1/1, PFS 5.5+ months). No unexpected toxicity occurred. CONCLUSIONS: Overall, 12 of 19 patients (63%) with advanced SGC, treated with chemotherapy-free regimens matched to specific molecular alterations, experienced an objective response. Data from MyPathway suggest that matched targeted therapy for SGC has promising efficacy, supporting molecular profiling in treatment determination.

Coexistence of the BRCA1 and KRAS mutations in a patient with salivary gland carcinoma arising in mediastinal mature teratoma.

Teratoma with malignant transformation is a rare type of malignant teratoma. In the present case, we describe a patient with salivary gland carcinoma (SGC) generating in mediastinal mature teratoma. Next-generation sequencing showed BRCA1 and KRAS somatic mutations, which might be associated with malignant transformation of the mediastinal mature teratomas. To our knowledge, the present case is the first report of coexistence of BRCA1 and KRAS mutations in mature cystic teratoma with malignant transformation to SGC. And the tumor showed a good response to chemotherapy with cisplatin and paclitaxel according to the transformed histology.

Exosomes and other extracellular vesicles in oral and salivary gland cancers.

Extracellular vesicles (EVs, including exosomes) are a group of heterogeneous nanometer-sized vesicles that are released by all types of cells and serve as functional mediators of cell-to-cell communication. This ability is primarily due to their capacity to package and transport various proteins, lipids, and nucleic acids-namely DNA and messenger RNA (mRNA), but also microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). These contents can influence the function and fate of both recipient and donor cells. More and more studies have shown that EVs are involved in every phase of cancer development, mediating bidirectional cross talk between cancer cells and their tissue microenvironment. More specifically, EVs can promote tumor progression by modifying vesicular contents and establishing a distant premetastatic niche with molecules that favor cancer cell proliferation, migration, invasion, metastasis, angiogenesis, and even drug resistance. Given that the packaging of these molecules is known to be tissue-specific, EVs can not only serve as novel prognostic and diagnostic markers but also be used as potential therapeutic targets and vehicles for drug delivery. The present review discusses the current understanding of the multifaceted roles of EVs in the progression of oral and salivary gland cancers, as well as their potential use in clinical applications.

The Impact of Angiogenesis in the Most Common Salivary Gland Malignant Tumors.

Salivary gland carcinomas (SGCs) represent a group of rare tumors, with complete surgical resection being the main treatment option. Therapeutic armory for cases of locally aggressive, recurrent, and/or metastatic SGCs, though, remains poor since they exhibit high rates of resistance to systematic therapy. Angiogenesis is considered one of the contemporary hallmarks of cancer and anti-angiogenic factors have already been approved for the treatment of several cancer types. This review aims to summarize, in a histotype-specific manner, the most current available data on the angiogenic factors implicated in SGC angiogenesis, in order to highlight the differences between the most common SGC histotypes and the factors that may have a potential role as therapeutic targets.

JQ1 and PI3K inhibition synergistically reduce salivary adenoid cystic carcinoma malignancy by targeting the c-Myc and EGFR signaling pathways.

BACKGROUND: To investigate the therapeutic mechanism of the BRD4 inhibitor JQ1 in SACC-83 cells and explore strategies to enhance its therapeutic potential. MATERIAL AND METHODS: SACC-83 cells were used in the experiment. Immunohistochemistry was used to assess BRD4 expression in SACC tissues and corresponding adjacent non-tumor tissues. Cell viability and proliferation were evaluated using the Cell Counting Kit-8 assay. Flow cytometry was used to quantitate apoptosis. Levels of cleaved caspase-3, BRD4, c-Myc, pEGFR (γ-1173), and EGFR were determined by quantitative real-time PCR and Western blot. To study the role of EGFR in JQ1 resistance, we generated EGFR knockdown SACC-83 cells by siRNA transfection. RESULTS: Our study revealed that BRD4 was overexpressed and could be a treatment target in SACC. The BRD4 inhibitor JQ1 markedly inhibited c-Myc expression in SACC-83 cells, which produced modest therapeutic effects. Nevertheless, the EGFR pathway was strongly activated following JQ1 treatment, which led to JQ1 resistance. Combined JQ1 and PI3K inhibitor treatment effectively increased the therapeutic potential by inhibiting the EGFR and c-Myc signaling pathways in SACC-83 cells. Moreover, EGFR knockdown sensitized SACC-83 cells to JQ1. CONCLUSION: These data demonstrate that EGFR and c-Myc signaling synergistically drive SACC progression. The JQ1 and PI3K inhibitor combination exhibited a strong synergistic effect by suppressing c-Myc and EGFR in SACC-83 cells, identifying a novel rational combinatorial treatment. Moreover, EGFR expression influences the sensitivity of SACC-83 cells to JQ1, which is useful for planning treatment.