Secreted cystatins decrease proliferation and enhance apoptosis of human leukemic cells

Research output: Contribution to journalArticle

Standard

Secreted cystatins decrease proliferation and enhance apoptosis of human leukemic cells. / Hunaiti, Samar; Wallin, Hanna; Eriksson, Mia; Järås, Marcus; Abrahamson, Magnus.

In: FEBS Open Bio, Vol. 10, No. 10, 01.10.2020, p. 2166-2181.

Research output: Contribution to journalArticle

Harvard

APA

CBE

MLA

Vancouver

Author

RIS

TY - JOUR

T1 - Secreted cystatins decrease proliferation and enhance apoptosis of human leukemic cells

AU - Hunaiti, Samar

AU - Wallin, Hanna

AU - Eriksson, Mia

AU - Järås, Marcus

AU - Abrahamson, Magnus

PY - 2020/10/1

Y1 - 2020/10/1

N2 - Cysteine proteases are implicated in proteolysis events favoring cancer cell growth, spread, and death by apoptosis. Herein, we have studied whether the net growth and survival of the leukemic cell lines Jurkat, U937, and HL-60 are affected by external addition of five proteins acting as natural cysteine protease inhibitors. None of the cystatins examined (A, C, D, and E/M) or chagasin showed consistent effects on Fas-induced apoptosis when evaluated at 1 µm. In contrast, when the intrinsic apoptosis pathway was activated by hydrogen peroxide, addition of cystatin D augmented caspase-3-like activity within all three cell lines. Flow cytometric analysis of U937 cells also showed increased numbers of annexin V-positive cells when hydrogen peroxide was used to initiate apoptosis and cells were cultured in the presence of cystatin D or C. Moreover, stimulation of hydrogen peroxide-induced apoptotic U937 cells with either cystatin C or D resulted in a dose-dependent decrease in the number of cells. Cell viability was also decreased when U937 cells were cultured in the presence of cystatin C or D (1–9 µm) only, demonstrating that these cystatins can reduce cell proliferation by themselves in addition to enhancing apoptosis induced by oxidative stress. These effects on U937 cells were paralleled by internalization of cystatins C and D, indicating these effects are caused by downregulation of intracellular proteolysis. External addition of cystatins C and D to HL-60 and Jurkat cells demonstrated similar degrees of cystatin D uptake and decreased viability as for U937 cells, indicating that these effects are general for leukemic cells.

AB - Cysteine proteases are implicated in proteolysis events favoring cancer cell growth, spread, and death by apoptosis. Herein, we have studied whether the net growth and survival of the leukemic cell lines Jurkat, U937, and HL-60 are affected by external addition of five proteins acting as natural cysteine protease inhibitors. None of the cystatins examined (A, C, D, and E/M) or chagasin showed consistent effects on Fas-induced apoptosis when evaluated at 1 µm. In contrast, when the intrinsic apoptosis pathway was activated by hydrogen peroxide, addition of cystatin D augmented caspase-3-like activity within all three cell lines. Flow cytometric analysis of U937 cells also showed increased numbers of annexin V-positive cells when hydrogen peroxide was used to initiate apoptosis and cells were cultured in the presence of cystatin D or C. Moreover, stimulation of hydrogen peroxide-induced apoptotic U937 cells with either cystatin C or D resulted in a dose-dependent decrease in the number of cells. Cell viability was also decreased when U937 cells were cultured in the presence of cystatin C or D (1–9 µm) only, demonstrating that these cystatins can reduce cell proliferation by themselves in addition to enhancing apoptosis induced by oxidative stress. These effects on U937 cells were paralleled by internalization of cystatins C and D, indicating these effects are caused by downregulation of intracellular proteolysis. External addition of cystatins C and D to HL-60 and Jurkat cells demonstrated similar degrees of cystatin D uptake and decreased viability as for U937 cells, indicating that these effects are general for leukemic cells.

KW - caspase-3

KW - cystatin C

KW - cystatin D

KW - cysteine peptidase

KW - cysteine protease

KW - protease inhibitor

U2 - 10.1002/2211-5463.12958

DO - 10.1002/2211-5463.12958

M3 - Article

C2 - 32810913

AN - SCOPUS:85091318537

VL - 10

SP - 2166

EP - 2181

JO - FEBS Open Bio

JF - FEBS Open Bio

SN - 2211-5463

IS - 10

ER -