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Simple Summary: The transcription factor p53 is a crucial tumor suppressor that regulates diverse cellular responses to protect against cancer development. Deactivating p53 signaling either by altering p53 regulators or by p53 mutations occurs frequently in human colorectal carcinoma (CRC). Forty-three percent of CRCs harbor p53 mutations that reduce wild-type p53 tumor suppressor activity and often provide neo-morphic functions, which contribute to tumorigenesis. In this review, we summarize wild-type p53 signaling, how it can be deregulated in CRC, and the functional and phenotypical effects of p53 mutations. We also discuss current therapeutic strategies of targeting p53. The transcription factor p53 functions as a critical tumor suppressor by orchestrating a plethora of cellular responses such as DNA repair, cell cycle arrest, cellular senescence, cell death, cell differentiation, and metabolism. In unstressed cells, p53 levels are kept low due to its polyubiquitination by the E3 ubiquitin ligase MDM2. In response to various stress signals, including DNA damage and aberrant growth signals, the interaction between p53 and MDM2 is blocked and p53 becomes stabilized, allowing p53 to regulate a diverse set of cellular responses mainly through the transactivation of its target genes. The outcome of p53 activation is controlled by its dynamics, its interactions with other proteins, and post-translational modifications. Due to its involvement in several tumor-suppressing pathways, p53 function is frequently impaired in human cancers. In colorectal cancer (CRC), the TP53 gene is mutated in 43% of tumors, and the remaining tumors often have compromised p53 functioning because of alterations in the genes encoding proteins involved in p53 regulation, such as ATM (13%) or DNA-PKcs (11%). TP53 mutations in CRC are usually missense mutations that impair wild-type p53 function (loss-of-function) and that even might provide neo-morphic (gain-of-function) activities such as promoting cancer cell stemness, cell proliferation, invasion, and metastasis, thereby promoting cancer progression. Although the first compounds targeting p53 are in clinical trials, a better understanding of wild-type and mutant p53 functions will likely pave the way for novel CRC therapies. [ABSTRACT FROM AUTHOR]

Simple Summary: Epithelial ovarian cancer is one of the most lethal cancers in women and is typically diagnosed at an advanced-stage. Historically, primary tumor reductive surgery was attempted followed by postoperative chemotherapy in most patients diagnosed with advanced ovarian cancer. However, neoadjuvant chemotherapy followed by interval tumor reductive surgery is an alternative approach for patients with advanced-stage ovarian cancer where primary tumor reductive surgery is not feasible. Here, we review proposed models that can assist in selecting patients who would benefit most from neoadjuvant chemotherapy followed by surgery. Epithelial ovarian cancer remains a leading cause of death amongst all gynecologic cancers despite advances in surgical and medical therapy. Historically, patients with ovarian cancer underwent primary tumor reductive surgery followed by postoperative chemotherapy; however, neoadjuvant chemotherapy followed by interval tumor reductive surgery has gradually become an alternative approach for patients with advanced-stage ovarian cancer for whom primary tumor reductive surgery is not feasible. Decision-making about the use of these approaches has not been uniform. Hence, it is essential to identify patients who can benefit most from neoadjuvant chemotherapy followed by interval tumor reductive surgery. Several prospective and retrospective studies have proposed potential models to guide upfront decision-making for patients with advanced ovarian cancer. In this review, we summarize important decision-making models that can improve patient selection for personalized treatment. Models based on clinical factors (clinical parameters, radiology studies and laparoscopy scoring) and molecular markers (circulating and tumor-based) are useful, but laparoscopic staging is among the most informative diagnostic methods for upfront decision-making in patients medically fit for surgery. Further research is needed to explore more reliable models to determine personalized treatment for advanced epithelial ovarian cancer. [ABSTRACT FROM AUTHOR]