Increased mTORC2 pathway activation in lymph nodes of iMCD-TAFRO

© 2022 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd..

Idiopathic multicentric Castleman disease (iMCD) is a rare and life-threatening haematologic disorder involving polyclonal lymphoproliferation and organ dysfunction due to excessive cytokine production, including interleukin-6 (IL-6). Clinical trial and real-world data demonstrate that IL-6 inhibition is effective in 34-50% of patients. mTOR, which functions through mTORC1 and mTORC2, is a recently discovered therapeutic target. The mTOR inhibitor sirolimus, which preferentially inhibits mTORC1, has led to sustained remission in a small cohort of anti-IL-6-refractory iMCD patients with thrombocytopenia, anasarca, fever, renal dysfunction and organomegaly (iMCD-TAFRO). However, sirolimus has not shown uniform effect, potentially due to its limited mTORC2 inhibition. To investigate mTORC2 activation in iMCD, we quantified the mTORC2 effector protein pNDRG1 by immunohistochemistry of lymph node tissue from six iMCD-TAFRO and eight iMCD patients who do not meet TAFRO criteria (iMCD-not-otherwise-specified; iMCD-NOS). mTORC2 activation was increased in all regions of iMCD-TAFRO lymph nodes and the interfollicular space of iMCD-NOS compared with control tissue. Immunohistochemistry also revealed increased pNDRG1 expression in iMCD-TAFRO germinal centres compared with autoimmune lymphoproliferative syndrome (ALPS), an mTOR-driven, sirolimus-responsive lymphoproliferative disorder, and comparable staining between iMCD-NOS and ALPS. These results suggest increased mTORC2 activity in iMCD and that dual mTORC1/mTORC2 inhibitors may be a rational therapeutic approach.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:26

Enthalten in:

Journal of cellular and molecular medicine - 26(2022), 11 vom: 02. Juni, Seite 3147-3152

Sprache:

Englisch

Beteiligte Personen:

Phillips, Alexis D [VerfasserIn]
Kakkis, Joseph J [VerfasserIn]
Tsao, Patricia Y [VerfasserIn]
Pierson, Sheila K [VerfasserIn]
Fajgenbaum, David C [VerfasserIn]

Links:

Volltext

Themen:

Autoimmune lymphoproliferative syndrome
Castleman disease
EC 2.7.11.1
IMCD
Idiopathic multicentric Castleman disease
Interleukin-6
Journal Article
MTOR
MTORC2
Mechanistic Target of Rapamycin Complex 1
Mechanistic Target of Rapamycin Complex 2
PNDRG1
Research Support, N.I.H., Extramural
Sirolimus
TAFRO
TOR Serine-Threonine Kinases
W36ZG6FT64

Anmerkungen:

Date Completed 08.06.2022

Date Revised 25.07.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1111/jcmm.17251

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM340175206