Mol Med Rep 18: [Related article:] 1095-1193, 2018; DOI:
10.3892/mmr.2018.9042
Following the publication of the above article, an
interested reader drew to the authors’ attention that they had
mentioned that activated PKCδ phosphorylates IKKβ in order that
IKKβ is relocated to the plasma membrane, resulting in the
induction of mast cell degranulation; however, four references the
authors had included did not seem to support this statement. The
authors have re-examined their paper, and realized that the four
references the reader mentioned were indeed cited incorrectly, and
wish to rectify this error through revising the third paragraph in
the Discussion section, the References section, and an associated
figure (Fig. 6C) in order to avoid
any further misunderstandings on the part of the readership.
 | Figure 6.CRT inhibits the signalling pathways
of Lyn and Syk (A and B) RBL-2H3 cells were sensitised with
anti-DNP-IgE for 16 h followed by treatment with various
concentrations of CRT 30 min before DNP/BSA stimulation. Levels of
phosphorylated (A) Lyn and Syk, and (B) PLCγ, PKCδ and IKKβ were
determined by western blot analysis 1 h after DNP/BSA stimulation.
The relative ratio of phosphorylated protein to total protein
levels were quantified. (C) Schematic diagram indicates how CRT
suppresses mast cell degranulation. CRT, cryptotanshinone; DNP/IgE,
anti-dinitrophenyl IgE isotype; DNA/BSA, dinitrophenyl-bovine serum
albumin; PLCγ, phospholipase Cγ; PKC, phospho-protein kinase C;
IKK, IκB kinase; IgE, immunoglobulin E; Veh, vehicle; Syk, spleen
tyrosine kinase. |
First, the authors wish to revise the wording of the
third and fourth paragraphs of the Discussion, as featured on pp.
1101-1102, to the following (changed text is indicated in
bold):
‘We showed that CRT exerts anti-AD effect through
inhibition of the mast cell degranulation in mast cells. Upon
IgE/antigen stimulation, the immunoreceptor tyrosine-based
activation motif (ITAM) region of FcεRI receptor which is on the
mast cell surface is phosphorylated and the initial signalling
protein kinases Lyn and Syk are recruited to the ITAM (28,29).
Then, the activated Lyn and Syk leads to phosphorylation of the
transmembrane adaptor linker for activation of T cells (LAT).
Phosphorylated LAT which is a scaffold for multimolecular
signalling complexes and activates PLCγ through phosphorylation.
The activated PLCγ hydrolyses phosphatidylinositol biphosphate
(PIP2) to generate second signalling molecules IP3 and DAG,
which activate PKCs including PKCδ to induce the mast cell
degranulation (30,31). On the other hand, cross-linking of
FcεRI also activates IKKβ, which moves to the lipid raft
fractions and phosphorylates synaptosomal-associated protein 23
(SNAP-23) leading to degranulation (7). Since PKCδ phosphorylates
IKKα, but not IKKβ (32), it is not likely that two signalling
pathways are directly connected. In this study, novel function
of CRT on phosphorylations of Lyn/Syk kinases in mast cells is
elucidated for the first time. Furthermore, it is likely that this
inhibitory effect of CRT on Lyn/Syk kinases negatively affected
activities of their downstream signalling molecules including PLCγ,
PKCδ, and IKKβ, which leads to decrease in mast cell degranulation
by CRT treatment.
Besides the inhibitory effect of CRT on mast cell
degranulation, here we provide additional evidence that CRT exerts
anti-AD effects through inactivation of MAPK and NF-κB. It has been
reported that CRT regulates the activities of MAPK and NF-κB in
various cell types. In rhabdomyosarcoma, hepatoma, and breast
carcinoma, CRT activates MAPK p38/JNK and suppresses ERK1/2,
followed by caspase-independent apoptosis (10,33,34). In
chronic myeloid leukaemia cells, CRT enhances TNF-α-induced
apoptosis through the activation of MAPK p38 (35). In smooth
muscle cells, CRT exerts anti-migration/invasion effect as it
inhibits TNF-α/NF-κB signalling pathway (36).’
Secondly, the authors wish to make the following
changes to the Reference list: New references 30–32 have been
inserted to the list, as follows:
30. Ozawa K, Szallasi Z, Kazanietz MG, Blumberg PM,
Mischak H, Mushinski JF and Beaven MA: Ca2+-dependent
and Ca2+-independent isozymes of protein kinase C
mediate exocytosis in antigen-stimulated rat basophilic RBL-2H3
cell. J Biol Chem 268: 1749–1756, 1993.
31. Cho SH, Woo CH, Yoon SB and Kim JH: Protein
kinase Cδ functions downstream of Ca2+ mobilization in
FcεRI signaling to degranulation in mast cells. J Allergy Clin
Immunol 114: 1085–1092, 2004.
32. Yamaguchi T, Miki Y and Yoshida K: Protein
kinase Cδ activates IκB-kinase α to induce the p53 tumor suppressor
in response to oxidative stress. Cell Signal 19: 2088–2097,
2007.
The addition of these new references means that the
former references 30–33 have been accordingly renumbered to
references 33–36.
Finally, the authors have revised Fig. 6C, as it appeared on p. 1102, in
order to assist the understanding of the readers, and the corrected
version of Fig. 6 appears on the
next page. All these corrections have been approved by all the
authors, with the exception of the first author, Sumiyasuren
Buyanravjikh, who is no longer uncontactable. The authors regret
that these errors were included in the paper, even though they did
not substantially alter any of the major conclusions reported in
the study, are grateful to the Editor for allowing them this
opportunity to publish a Corrigendum, and apologize to the
readership for any inconvenience caused.
