Cancer cells rely on fatty acid synthase (FASN), a key enzyme for de novo biosynthesis of long chain fatty acids, to sustain their proliferative potential and drive invasion. Unfortunately, conventional FASN assays are technically inadequate for discerning otherwise elusive FASN activity in complex biological milieux, which has hindered progress in the functional study of FASN and development of its inhibitors. Here, we describe a chemical probe with unprecedented selectivity and sensitivity for the labeling of active FASN in living cells, thus demonstrating a new analytical modality for visualizing endogenous FASN activity and exploring opportunities for drug discovery.

Background: This work was designed to explore the roles of PIM-1 in the development of cervical cancer. Methods: There were 90 paired cervical tumor samples and the non-tumor adjacent tissue. The levels of PIM-1 in different samples were examined using quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) methods. The potential diagnostic value of PIM-1 was analyzed by the receiver operating characteristic (ROC) curve; furthermore, the expression of EGFR in tumor samples was detected, and Pearson’s correlation analysis was performed to analyze the relationship between the expression of PIM-1 and EGFR. Finally, cervical cancer cell line Hela cells were cultured and treated by PIM-1 siRNA, and MTT assay and Pi/Annexin V assay were performed to explore the effects of PIM-1 siRNA on the growth and apoptosis ability of the Hela cells. Results: PIM-1 was significantly up-regulated in cervical cancer tissue compared to adjacent tissue, and the expression of PIM-1 in patients with cervical cancer is positively associated with the size and metastasis of the tumor. ROC analysis showed PIM-1 is a sensitive biomarker for the diagnosis of cervical cancer. Furthermore, EGFR was over-expressed in cervical cancer tumor tissues, and the levels of PIM-1 and EGFR in cervical cancer tissue were positively correlated. Finally, PIM-1 siRNA dramatically inhibited the viability and promoted the apoptosis of the Hela cells. Conclusion: Our findings prove that PIM-1 may function as an oncogene in cervical cancer and can regulate the EGFR signaling in cervical cancer.

Selective profiling of steviol-catalyzing UDP-glycosyltransferases in plants was accomplished with a probe metabolically synthesized from two substrate-derived components comprising an alkynylated sugar receptor (steviol) module and a diazirine-modified sugar donor...

Cobalamin-independent methionine synthases (MS) are zinc-binding methyltransferases that catalyze de novo methionine biosynthesis in higher plants, which are enzymes critically involved in seed germination and plant growth. Here, we report a highly selective sulfonyl fluoride-based probe for chemoproteomic profiling of MS enzymes in living systems of the model plant Arabidopsis thaliana, as implemented in in-gel-, mass spectrometry-, and imaging-based platforms. This probe holds promise for facilitating and accelerating fundamental research and industrial application of MS enzymes, particularly in the contexts of MS1/2targeting herbicide screening and design.