TNFα increased the malignant behavior of tumor cell lines.44,45 TNFα knock-out mice are resistant to chemically induced skin carcinogenesis.46 TNFα increased chromosomal instability by virtue of its ability to induce ROS.47 Similarly, our study clearly demonstrated that chronic exposure to TNFα induced a malignant growth phenotype in HPV-immortalized keratinocytes but not in non-HPV-immortalized keratinocytes, i.e., OKF6/tert cells. This evidence concerns the gene TNF and neoplasm.