PIK3CA MUTATION

在乳腺癌、结直肠癌和头颈部鳞状细胞癌中，许多癌症中都观察到PIK3CA突变。这些突变分别在40%、20%和21%的这些癌症类型中观察到，突变通常发生在外显子20的螺旋外显子9和激酶域内。在乳腺癌中，PIK3CA突变与更好的预后和更高的生存率有关，然而PI3K通路也与耐药性增加有关（曲妥珠单抗/拉帕替尼）。hnscc和crc中的pik3ca突变与抗egfr治疗剂的耐药性有关，外显子9和20的突变与crc预后较差有关。有趣的是，在许多族群（包括希腊、德国和越南）中观察到HNSCC的PIK3CA突变不存在。
PIK3CA mutations are observed in many cancers among the most prevalent are breast cancer, colorectal cancer, and head and neck squamous cell carcinoma. These mutations have been observed in up to 40%, 20%, and 21% respectively for each of these cancer types with mutations commonly occurring within the helical exon 9 and kinase domain of exon 20. In breast cancer PIK3CA mutations have been associated with better prognosis, and a greater survival outcome, however the PI3K pathway is also associated with increased drug resistance (trastuzumab/lapatinib). PIK3CA mutations in both HNSCC and CRC have been associated with resistance to anti-EGFR therapeutic agents and mutations in exon 9 and 20 are associated with a poorer prognosis in CRC. Interestingly PIK3CA mutations in HNSCC have been observed to be absent from a number of ethnic groups including greek, german, and vietnamese populations.