CDKN2A and neoplasm: Quantitative correlations among SA‐β‐gal activity, p16INK4a expression, the senescence‐associated secretory phenotype (SASP) and single‐cell stiffness are still fragmentary, and no “aging‐mechanical fingerprint”—analogous to the universally recognized stiffening of tumor stroma—has yet been identified or therapeutically exploited.