Mitochondrial proteomics with siRNA knockdown to reveal ACAT1 and MDH2 in the development of doxorubicin‐resistant uterine cancer

Abstract

Mitochondria are key organelles in mammary cells in responsible for a number of cellular functions including cell survival and energy metabolism. Moreover, mitochondria are one of the major targets under doxorubicin treatment. In this study, low-abundant mitochondrial proteins were enriched for proteomic analysis with the state-of-the-art two-dimensional differential gel electrophoresis (2D-DIGE) and matrix-assistant laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) strategy to compare and identify the mitochondrial protein profiling changes in response to the development of doxorubicin resistance in human uterine cancer cells. The mitochondrial proteomic results demonstrate more than fifteen hundred protein features were resolved from the equal amount pooled of three purified mitochondrial proteins and 101 differentially expressed spots were identified. In which, 39 out of these 101 identified proteins belong to mitochondrial proteins. Mitochondrial proteins such as acetyl-CoA acetyltransferase (ACAT1) and malate dehydrogenase (MDH2) have not been reported with the roles on the formation of doxorubicin resistance in our knowledge. Further studies have used RNA interference and cell viability analysis to evidence the essential roles of ACAT1 and MDH2 on their potency in the formation of doxorubicin resistance through increased cell viability and decreased cell apoptosis during doxorubicin treatment. To sum up, our current mitochondrial proteomic approaches allowed us to identify numerous proteins, including ACAT1 and MDH2, involved in various drug-resistance-forming mechanisms. Our results provide potential diagnostic markers and therapeutic candidates for the treatment of doxorubicin-resistant uterine cancer.

Identification and validation of potential prognostic gene biomarkers for predicting survival in patients with acute myeloid leukemia

“… 36 Previous studies also indicated that MDH2 was involved in prostate and uterine cancer chemotherapy resistance. 37 , 38 There was a marked upregulation of MDH2 expression in prostate tumor tissue, and knockdown of MDH2 in prostate cancer cell lines significantly inhibited cell proliferation and increased the sensitivity of docetaxel. 37 A study by Liu et al 37 also observed that overexpression of MDH2 significantly increased the risk of prostate cancer recurrence after receiving neoadjuvant chemotherapy.…”

Tetrameric Acetyl-CoA Acetyltransferase 1 Is Important for Tumor Growth

“…Moreover, AH inhibits cell proliferation of diverse human cancer cells and primary leukemia cells from human patients as well as tumor growth of xenograft nude mice with no obvious off target effect and minimal toxicity. In addition, Lo et al recently suggested that ACAT1 may confer doxorubicin resistance to uterine cancer cells (Lo et al, 2015). These data provide “proof of principle” to suggest targeting tetrameric ACAT1 as a promising therapy in the clinical treatment of human cancer patients with elevated ACAT1 activity and glycolysis rate, as well as relapsed cancer patients with chemo-resistance.…”

Metabolic Enzymes Moonlighting in the Nucleus: Metabolic Regulation of Gene Transcription

“…Malate Dehydrogenase (MDH) MDH2 produces oxaloacetate from malate and has also been detected in cancer cell nuclei, but its non-canonical function is unknown [58,63]. MDH1, the cytoplasmic isoenzyme, translocates in the nucleus under low-glucose conditions, promoting p53-mediated cell-cycle arrest and apoptosis [58,64].…”