The role of pemetrexed in recurrent epithelial ovarian cancer: A scoping review

Targeting Oncometabolites in Peritoneal Cancers: Preclinical Insights and Therapeutic Strategies

Peritoneal cancers present significant clinical challenges with poor prognosis. Understanding the role of cancer cell metabolism and cancer-promoting metabolites in peritoneal cancers can provide new insights into the mechanisms that drive tumor progression and can identify novel therapeutic targets and biomarkers for early detection, prognosis, and treatment response. Cancer cells dynamically reprogram their metabolism to facilitate tumor growth and overcome metabolic stress, with cancer-promoting metabolites such as kynurenines, lactate, and sphingosine-1-phosphate promoting cell proliferation, angiogenesis, and immune evasion. Targeting cancer-promoting metabolites could also lead to the development of effective combinatorial and adjuvant therapies involving metabolic inhibitors for the treatment of peritoneal cancers. With the observed metabolomic heterogeneity in cancer patients, defining peritoneal cancer metabolome and cancer-promoting metabolites holds great promise for improving outcomes for patients with peritoneal tumors and advancing the field of precision cancer medicine. This review provides an overview of the metabolic signatures of peritoneal cancer cells, explores the role of cancer-promoting metabolites as potential therapeutic targets, and discusses the implications for advancing precision cancer medicine in peritoneal cancers.

Folate Transport and One-Carbon Metabolism in Targeted Therapies of Epithelial Ovarian Cancer

New therapies are urgently needed for epithelial ovarian cancer (EOC), the most lethal gynecologic malignancy. To identify new approaches for targeting EOC, metabolic vulnerabilities must be discovered and strategies for the selective delivery of therapeutic agents must be established. Folate receptor (FR) α and the proton-coupled folate transporter (PCFT) are expressed in the majority of EOCs. FRβ is expressed on tumor-associated macrophages, a major infiltrating immune population in EOC. One-carbon (C1) metabolism is partitioned between the cytosol and mitochondria and is important for the synthesis of nucleotides, amino acids, glutathione, and other critical metabolites. Novel inhibitors are being developed with the potential for therapeutic targeting of tumors via FRs and the PCFT, as well as for inhibiting C1 metabolism. In this review, we summarize these exciting new developments in targeted therapies for both tumors and the tumor microenvironment in EOC.

Cellular Fitness Phenotypes of Cancer Target Genes from Oncobiology to Cancer Therapeutics

To define the growing significance of cellular targets and/or effectors of cancer drugs, we examined the fitness dependency of cellular targets and effectors of cancer drug targets across human cancer cells from 19 cancer types. We observed that the deletion of 35 out of 47 cellular effectors and/or targets of oncology drugs did not result in the expected loss of cell fitness in appropriate cancer types for which drugs targeting or utilizing these molecules for their actions were approved. Additionally, our analysis recognized 43 cellular molecules as fitness genes in several cancer types in which these drugs were not approved, and thus, providing clues for repurposing certain approved oncology drugs in such cancer types. For example, we found a widespread upregulation and fitness dependency of several components of the mevalonate and purine biosynthesis pathways (currently targeted by bisphosphonates, statins, and pemetrexed in certain cancers) and an association between the overexpression of these molecules and reduction in the overall survival duration of patients with breast and other hard-to-treat cancers, for which such drugs are not approved. In brief, the present analysis raised cautions about off-target and undesirable effects of certain oncology drugs in a subset of cancers where the intended cellular effectors of drug might not be good fitness genes and that this study offers a potential rationale for repurposing certain approved oncology drugs for targeted therapeutics in additional cancer types.

Facile Synthetic Protocols for the preparation of New Impurities in Pemetrexed Disodium Heptahydrate as an Anti-Cancer Drug

A facile synthetic protocols were employed to prepare process-related impurities associated with the synthesis of pemetrexed disodium heptahydrate, Alimta. The research work is described for the development of the novel synthetic methods and their structure elucidation of Pemetrexed glutamide, N-methyl pemetrexed, and N-methyl pemetrexed glutamide impurities. The listed impurities were deduced through spectral analysis such as 1H-NMR, 13CNMR, and HRMS. The target compounds can be used as the reference substances for the quality control.

Establishment and characterization of a new malignant peritoneal mesothelioma cell line, KOG-1, from the ascitic fluid of a patient with pemetrexed chemotherapy resistance

Malignant peritoneal mesothelioma (MPeM) is a rare and aggressive form of malignant mesothelioma. Sufficient biological tools for studying the functional characteristics of this cancer have not been developed. Therefore, in this study, a novel human cancer cell line, KOG-1, was established from ascites fluids isolated from a 39-year-old Japanese woman with pemetrexed-resistant MPeM. Cells were dendritic or linear immediately after thawing, showed a jigsaw puzzle-like and spindle arrangement during growth, and formed monolayers without contact inhibition in two-dimensional (2D) culture. The population doubling time was 13.7 h. Karyotypic and molecular genetic analyses showed that chromosome numbers ranged from 62 to 142, with a peak of 73 with complicated copy number alterations. No germline BAP1 pathogenic variant was detected. Cells expressed various tumor markers of mesothelioma, such as calretinin, podoplanin, and Wilms tumor 1 (WT-1). Drug sensitivity and resistance testing with a set of 36 drugs using 2D and three-dimensional (3D) culture models demonstrated that KOG-1 cells showed high and low sensitivity to pemetrexed under 2D and 3D culture conditions, respectively, whereas control ovarian cancer cell lines showed low sensitivity to pemetrexed under both culture conditions. This newly established cell line will be a valuable biological resource to expand the feasibility of functional studies as well as drug testing for potential therapeutic purposes in MPeM.