PGRMC1 and cancer: As many studies reported that HNSC with concurrent mutation of multiple PI3K pathway genes were advanced (stage IV), implicating concerted PI3K pathway aberrations in HNSC progression (Qiu et al., 2006; Lui et al., 2013), these data revealed the positive correlation between PGRMC1 over-expression and PIK3CA genomic alterations, known for its association of cancer progression and metastasis, which provided further support for the oncogenic role of PGRMC1 and the potential interaction with PIK3CA.