[Chemical targeting of DNA and histone methylation in cancer: Novelties, hopes and promises]

Diagnostic and Therapeutic Perspectives Associated to Cobalamin-Dependent Metabolism and Transcobalamins’ Synthesis in Solid Cancers

Cobalamin or vitamin B12 (B12) is a cofactor for methionine synthase and methylmalonyl-CoA mutase, two enzymes implicated in key pathways for cell proliferation: methylation, purine synthesis, succinylation and ATP production. Ensuring these functions in cancer cells therefore requires important cobalamin needs and its uptake through the transcobalamin II receptor (TCII-R). Thus, both the TCII-R and the cobalamin-dependent metabolic pathways constitute promising therapeutic targets to inhibit cancer development. However, the link between cobalamin and solid cancers is not limited to cellular metabolism, as it also involves the circulating transcobalamins I and II (TCI or haptocorrin and TCII) carrier proteins, encoded by TCN1 and TCN2, respectively. In this respect, elevations of B12, TCI and TCII concentrations in plasma are associated with cancer onset and relapse, and with the presence of metastases and worse prognosis. In addition, TCN1 and TCN2 overexpressions are associated with chemoresistance and a proliferative phenotype, respectively. Here we review the involvement of cobalamin and transcobalamins in cancer diagnosis and prognosis, and as potential therapeutic targets. We further detail the relationship between cobalamin-dependent metabolic pathways in cancer cells and the transcobalamins’ abundancies in plasma and tumors, to ultimately hypothesize screening and therapeutic strategies linking these aspects.

Optical Imaging of Epigenetic Modifications in Cancer: A Systematic Review

Increasing evidence has demonstrated that abnormal epigenetic modifications are strongly related to cancer initiation. Thus, sensitive and specific detection of epigenetic modifications could markedly improve biological investigations and cancer precision medicine. A rapid development of molecular imaging approaches for the diagnosis and prognosis of cancer has been observed during the past few years. Various biomarkers unique to epigenetic modifications and targeted imaging probes have been characterized and used to discriminate cancer from healthy tissues, as well as evaluate therapeutic responses. In this study, we summarize the latest studies associated with optical molecular imaging of epigenetic modification targets, such as those involving DNA methylation, histone modification, noncoding RNA regulation, and chromosome remodeling, and further review their clinical application on cancer diagnosis and treatment. Lastly, we further propose the future directions for precision imaging of epigenetic modification in cancer. Supported by promising clinical and preclinical studies associated with optical molecular imaging technology and epigenetic drugs, the central role of epigenetics in cancer should be increasingly recognized and accepted.