Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
Compound
Query: EC:2.7.1.1 (
hexokinase
)
5,274
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The activities of the key glycolytic enzymes phosphofructokinase (PFK), pyruvate kinase (PK) and
hexokinase
in addition to adenosine deaminase, purine nucleoside phosphorylase (PNP) and lactate dehydrogenase (LDH) have been measured in lymphocytes from 39 cases with B-chronic lymphocytic leukaemia (B-CLL). According to the percentage of circulating large non-granular atypical lymphocytes (AL) the B-
CLL
cases were classified as: typical (less than 10% of AL; 28 cases) and atypical (10-25% AL; 11 cases). In both groups the median lymphocyte volume (MLV) was assessed and correlated with the correspondent enzyme activities. The MLV of B-
CLL
lymphocytes was significantly (p less than 0.001) decreased (149.9 +/- 19.4 fl) as compared to normal B lymphocytes (175.1 +/- 14.5 fl) and it was significantly (p less than 0.001) lower in typical B-
CLL
(141.8 +/- 12.2 fl) than in atypical B-
CLL
(172.0 +/- 17.2 fl). Furthermore, in patients with typical B-
CLL
, all enzyme activities when expressed as U/10(9) cells were, with the exception of PFK, significantly decreased compared to normal B lymphocytes. However, when the results were expressed as U/ml cells, only PK, PNP and LDH remained significantly low. These findings demonstrate that the determination of MLV in addition to morphology may be a useful tool to distinguish the two previously described morphological B-CLL variants (typical and atypical) and that these two different B-
CLL
groups are also distinguishable on the basis of three enzyme activities, PK, PNP and LDH which have been shown to be less dependent on cell size than the other enzymes, also studied here.
...
PMID:Relationship between lymphocyte size and enzyme activities in two morphological variants of B-chronic lymphocytic leukaemia. 252 63
The enzyme activities and isozyme distribution of the three glycolytic regulator enzymes
hexokinase
, phosphofructokinase and pyruvate kinase were studied in lymphocytes of patients with
chronic lymphocytic leukemia
. Isozyme distribution patterns were determined by kinetic measurements, electrophoresis and immunoprecipitation. The
CLL
lymphocytes were different from normal non-T lymphocytes with respect to
hexokinase
residual activity in the presence of glucose-1,6-P2, pyruvate kinase residual activity in the presence of alanine, and phosphofructokinase activity after stimulation by glucose-1,6-P2. No differences could be discerned in enzyme activities between the
CLL
and the normal T and non-T lymphocytes.
...
PMID:Isozyme distribution of hexokinase, phosphofructokinase and pyruvate kinase in lymphocytes from patients with chronic lymphocytic leukemia. 621 89
Voltage-dependent anion channel(VDAC)is mainly located on the outer mitochondrial membrane. High-resolution atomic force microscopy topography shows an eye-shaped VDAC with 3.8 nm x 2.7 nm pore dimensions. New work suggests pore formation by the assembly of homo-oligomers and supramolecule of VDAC or hetero oligomers composed of VDAC and pro-apoptotic proteins, such as Bax. The oligomeric VDAC pore allows for release of cytochrome C. Thus, VDAC plays a central role in the cell life and apoptosis. It has been shown that the
hexokinase
(HK)-VDAC1 interaction is critical for preventing induction of apoptosis in tumor cells. VDACs are expressed more highly in cancer cells than normal cells, thus can be used as the target in chemotherapy for cancer. VDAC is also involved in pathogenesis of hematological malignancies such as myeloma and
chronic lymphocytic leukemia
. Following identification of sequence and structure of VDAC, studies have focused on VDAC as important pharmacological target for new anticancer therapy. To induce apoptosis, agents directly interact with VDAC or detach HK from VDAC to disrupt the anti-apoptosis activity of VDAC-HK interaction, such as methyl jasmonate (MJ) and VDAC1-based peptides. In this review, the function, modulation, structure and location of the VDAC, progress of its researches in hematological malignancies and potential as targets of anti-cancer drugs are summarized.
...
PMID:[Voltage-dependent anion channel and hematological malignancies]. 2013 59
The voltage-dependent anion channel 1 (VDAC1), localized in the outer mitochondrial membrane, mediates metabolic cross-talk between the mitochondrion and the cytoplasm and thus serves a fundamental role in cell energy metabolism. VDAC1 also plays a key role in mitochondria-mediated apoptosis, interacting with anti-apoptotic proteins. Resistance of cancer cells to apoptosis involves quenching the mitochondrial apoptotic pathway by over-expression of anti-apoptotic/pro-survival
hexokinase
(HK) and Bcl-2 family proteins, proteins that mediate their anti-apoptotic activities via interaction with VDAC1. Using specifically designed VDAC1-based cell-penetrating peptides, we targeted these anti-apoptotic proteins to prevent their pro-survival/anti-apoptotic activities. Anti-apoptotic proteins are expressed at high levels in B-cell chronic lymphocytic leukemia (
CLL
), an incurable disease requiring innovative new approaches to improve therapeutic outcome.
CLL
is characterized by a clonal accumulation of mature neoplastic B cells that are resistant to apoptosis. Specifically, we demonstrate that the VDAC1-based peptides (Antp-LP4 and N-Terminal-Antp) selectively kill peripheral blood mononuclear cells (PBMCs) obtained from
CLL
patients, yet spare those obtained from healthy donors. The cell death induction competence of the peptides was well correlated with the amount of double positive CD19/CD5 cancerous
CLL
PBMCs, further illustrating their selectivity toward cancer cells. Moreover, these VDAC1-based peptides induced apoptosis by activating the mitochondria-mediated pathway, reflected in membrane blebbing, condensation of nuclei, DNA fragmentation, release of mitochondrial cytochrome c, loss of mitochondrial membrane potential, decreased cellular ATP levels and detachment of HK, all leading to apoptotic cell death. Thus, the mode of action of the peptides involves decreasing energy production and inducing apoptosis. Over 27 versions of cell-penetrating VDAC1-based peptides were designed and screened to identify the most stable, short and apoptosis-inducing peptides toward
CLL
-derived lymphocytes. In this manner, three optimized peptides suitable for in vivo studies were identified. This study thus reveals the potential of VDAC1-based peptides as an innovative and effective anti-
CLL
therapy.
...
PMID:VDAC1-based peptides: novel pro-apoptotic agents and potential therapeutics for B-cell chronic lymphocytic leukemia. 2405 77
Cancer cells undergo changes in metabolic and survival pathways that increase their malignancy. Isoform 2 of the glycolytic enzyme
hexokinase
(HK2) enhances both glucose metabolism and resistance to death stimuli in many neoplastic cell types. Here, we observe that HK2 locates at mitochondria-endoplasmic reticulum (ER) contact sites called MAMs (mitochondria-associated membranes). HK2 displacement from MAMs with a selective peptide triggers mitochondrial Ca
2+
overload caused by Ca
2+
release from ER via inositol-3-phosphate receptors (IP3Rs) and by Ca
2+
entry through plasma membrane. This results in Ca
2+
-dependent calpain activation, mitochondrial depolarization and cell death. The HK2-targeting peptide causes massive death of
chronic lymphocytic leukemia
B cells freshly isolated from patients, and an actionable form of the peptide reduces growth of breast and colon cancer cells allografted in mice without noxious effects on healthy tissues. These results identify a signaling pathway primed by HK2 displacement from MAMs that can be activated as anti-neoplastic strategy.
...
PMID:Hexokinase 2 displacement from mitochondria-associated membranes prompts Ca
2+
-dependent death of cancer cells. 3238 45