OncogenicPIK3CAMutation and Dysregulation in Human Salivary Duct Carcinoma

[摘要] Salivary duct carcinoma (SDC) is an aggressive malignant tumor with a high mortality, which resembles high-grade breast ductal carcinoma in morphology. The parotid gland is the most common location. Its molecular genetic characteristics remain largely unknown. We have previously reported high incidence ofPIK3CAsomatic mutations in head and neck squamous cell carcinoma, particularly in pharyngeal cancers. Here we examined thePIK3CAgene expression status and hotspot mutations in six cases of SDC by immunohistochemistry and genomic DNA sequencing. Immunohistochemistry showed thatPIK3CAexpression was elevated in all six patients with SDC. By DNA sequencing, two hotspot mutations of thePIK3CAgene, E545K (exon 9) and H1047R (exon 20), were identified in two of the six cases. Our results support that oncogenicPIK3CAis upregulated and frequently mutated in human SDC, adding evidence thatPIK3CAoncogenic pathway is critical in the tumorigenesis of SDC, and may be a plausible drug target for this rare disease.

[学科分类] 基础医学