In this context, the SALL4 (Spalt-Like Transcription Factor 4), LIN28A (LIN28 homolog A), and KLF4 (Kruppel-like factor 4) proteins, which act as essential regulators of pluripotency and embryonic self-renewal and can mediate tumour progression and differentiation, are relevant biomarkers for the analysis of stem cells [14–16]. This evidence concerns the gene KLF4 and neoplasm.