TY - JOUR
T1 - H2S-induced S-sulfhydration of lactate dehydrogenase a (LDHA) stimulates cellular bioenergetics in HCT116 colon cancer cells
AU - Untereiner, Ashley A.
AU - Oláh, Gabor
AU - Módis, Katalin
AU - Hellmich, Mark R.
AU - Szabo, Csaba
N1 - Funding Information:
This work was supported by grants from the National Institutes of Health (R01 CA175803) and the Cancer Prevention Research Institute of Texas (DP150074).
Publisher Copyright:
© 2017 Elsevier Inc.
PY - 2017/7/15
Y1 - 2017/7/15
N2 - Cystathionine-β-synthase (CBS) is upregulated and hydrogen sulfide (H2S) production is increased in colon cancer cells. The functional consequence of this response is stimulation of cellular bioenergetics and tumor growth and proliferation. Lactate dehydrogenase A (LDHA) is also upregulated in various colon cancer cells and has been previously implicated in tumor cell bioenergetics and proliferation. In the present study, we sought to determine the potential interaction between the H2S pathway and LDH activity in the control of bioenergetics and proliferation of colon cancer, using the colon cancer line HCT116. Low concentrations of GYY4137 (a slow-releasing H2S donor) enhanced mitochondrial function (oxygen consumption, ATP production, and spare respiratory capacity) and glycolysis in HCT116 cells. SiRNA-mediated transient silencing of LDHA attenuated the GYY4137-induced stimulation of mitochondrial respiration, but not of glycolysis. H2S induced the S-sulfhydration of Cys163 in recombinant LDHA, and stimulated LDHA activity. The H2S-induced stimulation of LDHA activity was absent in C163A LDHA. As shown in HCT116 cell whole extracts, in addition to LDHA activation, GYY4137 also stimulated LDHB activity, although to a smaller extent. Total cellular lactate and pyruvate measurements showed that in HCT116 cells LDHA catalyzes the conversion of pyruvate to lactate. Total cellular lactate levels were increased by GYY4137 in wild-type cells (but not in cells with LDHA silencing). LDHA silencing sensitized HCT116 cells to glucose oxidase (GOx)-induced oxidative stress; this was further exacerbated with GYY4137 treatment. Treatment with low concentrations of GYY4137 (0.3 mM) or GOx (0.01 U/ml) significantly increased the proliferation rate of HCT116 cells; the effect of GOx, but not the effect of GYY4137 was attenuated by LDHA silencing. The current report points to the involvement of LDHA in the stimulatory effect of H2S on mitochondrial respiration in colon cancer cells and characterizes some of the functional interactions between LDHA and H2S-stimulated bioenergetics under resting conditions, as well as during oxidative stress.
AB - Cystathionine-β-synthase (CBS) is upregulated and hydrogen sulfide (H2S) production is increased in colon cancer cells. The functional consequence of this response is stimulation of cellular bioenergetics and tumor growth and proliferation. Lactate dehydrogenase A (LDHA) is also upregulated in various colon cancer cells and has been previously implicated in tumor cell bioenergetics and proliferation. In the present study, we sought to determine the potential interaction between the H2S pathway and LDH activity in the control of bioenergetics and proliferation of colon cancer, using the colon cancer line HCT116. Low concentrations of GYY4137 (a slow-releasing H2S donor) enhanced mitochondrial function (oxygen consumption, ATP production, and spare respiratory capacity) and glycolysis in HCT116 cells. SiRNA-mediated transient silencing of LDHA attenuated the GYY4137-induced stimulation of mitochondrial respiration, but not of glycolysis. H2S induced the S-sulfhydration of Cys163 in recombinant LDHA, and stimulated LDHA activity. The H2S-induced stimulation of LDHA activity was absent in C163A LDHA. As shown in HCT116 cell whole extracts, in addition to LDHA activation, GYY4137 also stimulated LDHB activity, although to a smaller extent. Total cellular lactate and pyruvate measurements showed that in HCT116 cells LDHA catalyzes the conversion of pyruvate to lactate. Total cellular lactate levels were increased by GYY4137 in wild-type cells (but not in cells with LDHA silencing). LDHA silencing sensitized HCT116 cells to glucose oxidase (GOx)-induced oxidative stress; this was further exacerbated with GYY4137 treatment. Treatment with low concentrations of GYY4137 (0.3 mM) or GOx (0.01 U/ml) significantly increased the proliferation rate of HCT116 cells; the effect of GOx, but not the effect of GYY4137 was attenuated by LDHA silencing. The current report points to the involvement of LDHA in the stimulatory effect of H2S on mitochondrial respiration in colon cancer cells and characterizes some of the functional interactions between LDHA and H2S-stimulated bioenergetics under resting conditions, as well as during oxidative stress.
KW - Anticancer
KW - Mitochondrial electron transport
KW - ROS
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U2 - 10.1016/j.bcp.2017.03.025
DO - 10.1016/j.bcp.2017.03.025
M3 - Article
C2 - 28404377
AN - SCOPUS:85017427977
SN - 0006-2952
VL - 136
SP - 86
EP - 98
JO - Biochemical Pharmacology
JF - Biochemical Pharmacology
ER -