TP53 and squamous cell carcinoma: In a study by Gao et al., examining p53 mutations through exons 5–8 in patients with squamous cell carcinoma and adenocarcinoma of the lung [15], it was shown that patients with adenocarcinoma expressed mutational hotspots at codons 248 and 249, whereas patients with squamous cell carcinoma had mutational events spread throughout exons 5–8.