Colorectal cancer (CRC) is one of the most common and fatal cancers worldwide. The carcinogenesis of CRC is based on a stepwise accumulation of mutations, leading either to an activation of oncogenes or a deactivation of suppressor genes. The loss of genetic stability triggers activation of proto-oncogenes (e.g., KRAS) and inactivation of tumor suppression genes, namely TP53 and APC, which together drive the transition from adenoma to adenocarcinoma. On the one hand, p53 mutations confer resistance to classical chemotherapy but, on the other hand, they open the door for immunotherapy, as p53-mutated tumors are rich in neoantigens. Aberrant function of the TP53 gene product, p53, also affects stromal and non-stromal cells in the tumor microenvironment. Cancer-associated fibroblasts together with other immunosuppressive cells become valuable assets for the tumor by p53-mediated tumor signaling. In this review, we address the manifold implications of p53 mutations in CRC regarding therapy, treatment response and personalized medicine.

Background: The collagen-rich tumor stroma plays a crucial role in biliary tract cancer (BTC). Collagen biomarkers of type I collagen (reC1M), type III collagen (PRO-C3), type IV collagen (C4G), type VIII collagen (PRO-C8), type XI collagen (PRO-C11), type XVII collagen (PRO-C17) and type VIII collagen (TUM) may be used as potential non-invasive biomarkers. Methods: We measured the seven biomarkers of collagen turnover in sera of 72 patients with BTC at baseline and after first and second chemotherapy cycle (CTX). Markers were also assessed in sera of 50 healthy controls and compared to levels of patients at baseline. The diagnostic and prognostic value of the markers was evaluated for overall survival (OS) and progression-free survival (PFS). Results: Patients had a median age of 65 years (IQR 57–70), while healthy controls were younger, with a median age of 46 years (IQR 38–54). The majority of patients (62%) were diagnosed with intrahepatic bile duct adenocarcinoma. Except C4G, all collagen turnover markers were significantly (p < 0.001) increased in serum from patients with BTC compared to healthy controls. PRO-C3 was the best marker to discriminate between patients with BTC and controls, reaching an area under a receiver operating characteristic (AUROC) of 0.98 (95% CI 0.95; 0.99) with a sensitivity (92%) and specificity (94%) balanced cutoff of 77.3 ng/ml. Patients with high levels (cohort separated by median split) of PRO-C8 (HR 2.85, 95% CI 1.42; 5.73) followed by C3M (HR 2.33, 95% CI 1.2; 4.5), PRO-C3 (HR 3.09, 95% CI 1.5; 6.36) and CA 19–9 (HR 2.52, 95% CI 1.37; 4.64) as reference biomarker had a shorter OS. Notably, only the novel marker PRO-C8 was also predictive of PFS (HR 3.26, 95% CI 1.53; 6.95). Associations with survival outcomes remained significant after adjusting for relevant risk factors (CA 19–9 and CEA at baseline, age, presence of metastases, weight, height and gender). Conclusion: The collagen turnover markers PRO-C8, C3M, PRO-C3 and the established biomarker CA 19–9 were prognostic for OS in patients with BTC while only PRO-C8 was also predictive for PFS. PRO-C3 showed the best diagnostic performance to discriminate between patients with BTC and controls. Trial registration: Trial registration number and date of registration NCT00661830 (NCT number) 15 April 2008 Trial registry The complete registry can found under: https://clinicaltrials.gov/study/NCT00661830?tab=table#administrative-information (last accessed 01/2025) Principal investigator and study sponsor Markus Moehler, MD Johannes Gutenberg University Mainz

Background Combination of fluoropyrimidines and a platinum derivative are currently standards for systemic chemotherapy in advanced adenocarcinoma of the stomach and gastroesophageal junction (GEJ). Nevertheless, individual likelihood for response to these therapeutic regimes remains uncertain. Even more, no predictive markers are available to determine which patients may benefit more from oxaliplatin versus cisplatin or vice versa. The new invasion and stem cell markers VEGFR-3 and CXCR4 have been linked prognostically with more aggressive esophagogastric cancer types. Thus, we aimed to assess correlations of VEGFR-3 and CXCR4 expression levels with clinical outcome in a randomized phase III study of patients with oxaliplatin/leucovorin/5-FU (FLO) versus cisplatin/leucovorin/5-FU (FLP). Methods The patients data examined in this study (n = 72) were from the collective of the FLO vs. FLP phase III AIO trial. Tumour tissues were stained via immunohistochemistry for VEGFR-3 and CXCR4 expression and results were evaluated by two independent, blinded investigators. Outcome parameter: Survival analysis was calculated for patients receiving FLO vs. FLP in relation to VEGFR-3 and CXCR4 expression. Results 54% and 36% of the examined tumour tissues showed strong positive expression of VEGFR-3 and CXCR4 respectively. No superiority of each regime was detected in terms of overall survival (OS) in the whole population. Patients with strong expression of CXCR4 on their tumour tissues profited more in terms of OS under the treatment of FLP (mOS: 28 vs 15 months, p = 0.05 respectively). Patients with negative VEGFR-3 and CXCR4 expression had a trend to live longer when FLO regime was applied (mOS: 22 vs. 9 months, p = 0.099 and 20 vs. 10 months, p = 0.073 respectively). In an exploratory analysis of patients older than 60 years at diagnosis, we observed a significant benefit in overall survival for VEGFR-3 and CXCR4-positive patients when treated with FLP (p = 0.002, p = 0.021 respectively). Conclusions CXCR4 positive patients profited in terms of OS from FLP, whereas FLO proved to be more effective in CXCR4 and VEGFR-3 negative patients. Our results suggest, despite the limited size of the study, a predictive value of these biomarkers concerning chemotherapy with FLP or FLO in advanced esophagogastric cancer.