Open Access
Lazzarini et al., J Chromatogr Sep Tech 2014, 5:5
DOI: 10.4172/2157-7064.1000239
Open Access
Volume 5 • Isse 5 • 1000239
J Chromatogr Sep Tech
ISSN: 2157-7064 JCGST, an open access journal
Analysis of Serum Sphingomyelin Species by Uflc-Ms/Ms in Patients
Affected with Monoclonal Gammopathy
Lazzarini A
1
, Floridi A
1
, Pugliese L
1
, Villani M
1
, Cataldi S
1
, Michela Codini
2
, Lazzarini R
1
, Beccari T
2
, Ambesi-Impiombato FS
3
, Curcio F
3
and
Albi E
1
*
1
Laboratory of Nuclear Lipid BioPathology, CRABiON, Perugia, Italy
2
Department of Pharmaceutical Science, University of Perugia, Italy
3
Department of Clinical and Biological Sciences, University of Udine, Italy
*Corresponding author: Albi E, Laboratory of Nuclear Lipid BioPathology,
CRABiON, Perugia, Italy; Tel: 0039-075-5173544; Fax: 0039-075-5173544
e-mail: elisabetta.albi@yahoo.com
Received September 11, 2014; Accepted September 11, 2014; Published
October 03, 2014
Citation: Lazzarini A, Floridi A, Pugliese L, Villani M, Cataldi S, et al. (2014)
Analysis of Serum Sphingomyelin Species by Ufc-Ms/Ms in Patients Affected
with Monoclonal Gammopathy. J Chromatogr Sep Tech 5: 239. doi:10.4172/2157-
7064.1000239
Copyright: © 2014 Lazzarini A, et al. This is an open-access article distributed
under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the
original author and source are credited.
Abstract
Cancer cells are hungry of cholesterol incorporated from serum with avidity and used to favour the expressions
of proteins involved in cell proliferation such as RNA polymerase II, STAT3, PKCz and cyclin D1. Numerous studies
have shown that exists a strong interaction between unesterifed cholesterol and saturated fatty acid sphingomyelin
which arises from the Van der Waals interaction. Since sphingomyelin and cholesterol association is responsible
for the formation of membrane lipid raft involved in cell signalling, we studied the possible hyposphingomyelinemia
associated to hypocholesterolemia in the patients with cancer. The blood of 23 patients with monoclonal gammopathy
were analyzed for cholesterol, 12:0 sphingomyelin, 16:0 sphingomyelin and 18:1sphingomyelin content. The
results demonstrated that only the patients with very low level of cholesterol (65-99 mg/dl) had low amount of
sphingomyelin and, in particular, of saturated sphingomyelin specie (16:0 sphingomyelin). The possibility that the
hypocholesterolemia in cancer was secondary to hyposphingomyelinemia was discussed.
Keywords: Cholesterol; Sphingomyelin; MS/MS-UFLC; Blood
lipids; monoclonal gammopathy
Introduction
Lipids are structural and functional molecules localized in cell
membranes and in the nucleus where interact with active chromatin
and play specifc roles in cell proliferation, diferentiation, apoptosis
and cancer [1]. Hypocholesterolemia is common in patients with
various malignant diseases since cancer cells are hungry of cholesterol
(CHO) [2]. In fact, CHO is incorporated in cancer cells from serum
with avidity and used to favour the expressions of proteins involved in
cell proliferation such as RNA polymerase II, STAT3, PKCz and cyclin
D1 [2]. In cells, CHO is not randomly distributed over the membranes
but forms lipid microdomains thank to its link with saturated fatty
acid of sphingomyelin (SM) by Van der Waals interaction [3]. Te lipid
microdomains, also known as lipid rafs, are platforms for specifc proteins
involved in cell signaling if they are localized in cell membrane and are
platforms for DNA duplication and transcription if they are associated
to the inner nuclear membrane [4,5]. It has been demonstrated that
lipid rafs play important mediating roles in cell migration, metastasis,
cell survival and tumor progression [6]. In particular CHO has an
important role in regulating the synthesis of invadopodia: protrusion
in the cell membrane of some cells, displaying properties of SM and
CHO-enriched membranes or lipid rafs frequently seen in invasive and
metastatic cancer cells that invade surrounding tissues [7]. It remains
unclear how the rafs are formed in cancer cells, i.e., if using lipids that
incorporate from the blood, reducing their physiological values. Tere
is evidence that low levels of serum CHO-phospholipids are associated
with the antiphospholipid antibodies in monoclonal gammopathy [8].
However, while the hypocholesterolemia is widely studied in cancer
nothing is known about the possible change in the content of SM in
the blood of cancer patients. Tus, we aimed to study the possible
association of hypocholesterolemia with hyposphingomyelinemia in
the patients with monoclonal gammopathy (MG). We analysed the
main species of SM by SM/SM-UFLC in order to highlight the changes
of saturated fatty acid SMs that interact specifcally with CHO.
Materials and Methods
Patients
Blood samples from patients afected by monoclonal gammopathy
(MG), with diagnosis from the “Laboratorio Centralizzato di analisi
chimico-cliniche Ospedale Silvestrini, Perugia”, were collected over a
24 month period. Young and without poor nutrition state or extremely
dietary control patients were chosen as experimental model. From all
patients (62), only those with a low level of total CHO (23 patients)
were analyzed. Te population was composed of 13 males and 10
females, average age was 36 yrs. Te control group was composed of 20
healthy blood donors: 12 males and 8 females, average age 39 yrs, with
normal serum CHO levels.
Lipid extraction
Lipid extraction was performed according to Matyash et al. [9]. 1
mL of serum was diluted with 1mL methanol. 3 mL ultra pure water and
3 mL methyl tert -butyl ether (MTBE) were added. Each Sample was
vortexed for 1 min and centrifuged at 3000 g for 5 min. Te supernatant
was recovered. Te extraction with MTBE was repeated on the pellet
and the supernatant was added to the frst. Te organic phase was dried
under nitrogen fow and resuspended in 500 µL of methanol.
Research Article
Journal of Chromatography
Separation Techniques
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ISSN: 2157-7064