Methods for treating oral cancers

A method for treating an oral cancer in a subject, comprising,

• (a) respectively obtaining a first and a second biological samples from a lesion site and a non-lesion site of the subject;
• (b) respectively measuring the expression levels of a biomarker in the first and the second biological samples by quantitative reverse transcription polymerase chain reaction (qRT-PCR) thereby obtaining a first expression level and a second expression level, wherein the biomarker is CHEK1 gene, PIK3CA gene, or PIK3CD gene;
• (c) determining the ratio of the first expression level to the second expression level;
• and
• (d) administering to the subject an effective amount of a checkpoint kinase 1 inhibitor or a phosphatidylinositol 3-kinase inhibitor when the biomarker is the CHEK1 gene, and the ratio determined in the step (c) is at least 1.7;
• or when the biomarker is the PIK3CA gene, and the ratio determined in the step (c) is at least 2.4;
• or when the biomarker is the PIK3CD gene, and the ratio determined in the step (c) is at least 3.1;
• wherein in the qRT-PCR,
• a primer pair of SEQ ID NOs:
• 1 and 2 is used for detecting the expression level of the CHEK1 gene:
• a primer pair of SEQ ID NOs:
• 3 and 4 is used for detecting the expression level of the PIK3CA gene;
• and
• a primer pair of SEQ ID NOs:
• 5 and 6 is used for detecting the expression level of the PIK3CD gene.