Real-World Experience of Palbociclib-Induced Adverse Events and Compliance With Complete Blood Count Monitoring in Women With Hormone Receptor-Positive/HER2-Negative Metastatic Breast Cancer.

Background: The cyclin-dependent kinase 4/6 inhibitor palbociclib has emerged as a novel therapeutic agent in metastatic breast cancer. Neutropenia is commonly observed, and thus stringent treatment guidelines regarding complete blood count (CBC) monitoring have been developed. The aim of this study was to provide a real-world experience of the toxicities associated with palbociclib therapy and to evaluate compliance with CBC monitoring.

Serum Immune System Biomarkers Neopterin and Interleukin-10 Are Strongly Related to Tryptophan Metabolism in Healthy Young Adults.

Background: Changes in tryptophan metabolism through the vitamin B-6-dependent kynurenine pathway have been linked to activation of the immune system.

Objective: We hypothesized that blood concentrations of tryptophan and its catabolites were associated with biomarkers relevant to inflammatory processes in healthy noninflamed subjects.

Methods: Healthy young adults (n = 737) aged 18-28 y without any known diseases or clinical evidence of inflammation provided blood samples for analysis of serum tryptophan/kynurenine metabolites, neopterin, C-reactive protein (CRP), and plasma pyridoxal 5'-phosphate (PLP) with LC-tandem mass spectrometry methodologies.

Tryptophan catabolism and vitamin B-6 status are affected by gender and lifestyle factors in healthy young adults.

Background: Abnormalities of tryptophan (Trp) metabolism through the kynurenine (Kyn) pathway have been reported in various diseases; however, nutritional and lifestyle factors that affect this pathway in healthy individuals are not well documented.

Objective: Our aim was to examine the effect of vitamin B-6 status and lifestyle factors including the use of vitamin B-6 supplements, alcohol, smoking, and oral contraceptives on Trp and its Kyn metabolites in a cohort of 2436 healthy young adults aged 18-28 y.

Methods: Anthropometric and lifestyle data were collected by questionnaire.