ABSTRACT
Objective: Metabolism, a basic need and biochemical process for cell survival and proliferation, is closely connected with the pathogenesis and progression of prostate cancer. Methods: A four-gene signature construct that includes CKM (CKM), CD38, Enoyl Coenzyme A(EHHADH), and Arginase 2(ARG2) was created by bioinformatics. Finally, hub genes were validated by IHC and in vitro experiments. Results: The results showed the AUCs of the logistic regression and neural networks diagnostic model for the diagnosis of two subtypes were 0.920 and 0.936, respectively. The risk score demonstrated by univariable and multivariable Cox analysis is an independent predictive component of the prognostic signature for DFS. According to immunohistochemical analyses, ARG2 and CD38 expression levels were considerably under-expressed, but CKM and EHHADH expression levels were significantly overexpressed. Furthermore, The expression of ARG2 was significantly down-regulated in the late Gleason score. Finally, we found that ARG2 is lowly expressed in prostate cancer cells. Furthermore, based on the effect of ARG2 on the malignant phenotype of PCa in vitro, we also found that ARG2 may be a tumor suppressor that plays an important role in inhibiting proliferation, migration, and invasion. Conclusions: These findings suggest that ARG2 has been tentatively identified as a new target for research into how PCa develops in metabolism and for the development of innovative targeted treatments.
ABSTRACT
INTRODUCTION: Obesity is a public health challenge worldwide. To maintain a healthy weight, dieting and lifestyle changes are the first-line interventions; however, these interventions are of poor compliance and may cause body composition changes, mainly skeletal muscle wasting (sarcopenia). Dietary supplements for improving body composition while inducing weight loss are therefore needed. ß-hydroxy-ß-methylbutyrate (HMB) has been proven to be effective for improving muscle mass and muscle strength in athletes, older adults and patients with cancer. We aim to evaluate the effectiveness and safety of HMB-enriched nutritional supplements for improving muscle mass and muscle function in obese adults during calorie restriction. METHOD AND ANALYSIS: A total of 72 Chinese adults with obesity will be randomised to receive HMB-enriched nutritional supplements (65 g/day) or a placebo for 12 weeks. Participants in both groups will also receive calorie restrictions based on the individualised nutrition guidance of dietitians. Participants and investigators will be blinded to the allocations. The primary outcome will be the mean change in whole-body skeletal muscle mass (measured by bioelectrical impedance analysis). The secondary outcomes will include the mean change of appendicular skeletal muscle mass, body fat mass, basal metabolic rate, phase angle, muscle function and serum biomarkers. The enrolment will commence in December 2021 and will proceed until March 2022. ETHICS AND DISSEMINATION: This protocol has been approved by the Biomedical Ethics Committee of West China Hospital (2021-771). All potential subjects will be required to sign a written informed consent. The results of this study will be reported in peer-reviewed academic journals and conferences. TRIAL REGISTRATION NUMBER: NCT04953936.
Subject(s)
Muscle, Skeletal , Valerates , Aged , Dietary Supplements , Double-Blind Method , Humans , Muscle, Skeletal/physiology , Obesity/drug therapy , Randomized Controlled Trials as Topic , Weight LossABSTRACT
Metformin is an oral drug widely used for the treatment of type 2 diabetes mellitus. Numerous studies have demonstrated the value of metformin in cancer treatment. However, for metformin to elicit effects on cancer often requires a high dosage, and any underlying mechanism for how to improve its inhibitory effects remains unknown. Here, we found that low mRNA expression of glycerol-3-phosphate dehydrogenase 1 (GPD1) may predict a poor response to metformin treatment in 15 cancer cell lines. In vitro and in vivo, metformin treatment alone significantly suppressed cancer cell proliferation, a phenotype enhanced by GPD1 overexpression. Total cellular glycerol-3-phosphate concentration was significantly increased by the combination of GPD1 overexpression and metformin treatment, which suppressed cancer growth via inhibition of mitochondrial function. Eventually, increased reactive oxygen species and mitochondrial structural damage was observed in GPD1-overexpressing cell lines treated with metformin, which may contribute to cell death. In summary, this study demonstrates that GPD1 overexpression enhances the anticancer activity of metformin and that patients with increased GPD1 expression in tumor cells may respond better to metformin therapy. SIGNIFICANCE: GPD1 overexpression enhances the anticancer effect of metformin through synergistic inhibition of mitochondrial function, thereby providing new insight into metformin-mediated cancer therapy.
Subject(s)
Glycerolphosphate Dehydrogenase/metabolism , Glycerophosphates/metabolism , Metformin/pharmacology , Neoplasms/drug therapy , Neoplasms/metabolism , A549 Cells , Adenosine Triphosphate/biosynthesis , Animals , Antineoplastic Agents/pharmacology , Cell Growth Processes/physiology , Cell Line, Tumor , Cell Respiration/physiology , Drug Synergism , Glycerolphosphate Dehydrogenase/biosynthesis , Glycerolphosphate Dehydrogenase/genetics , HCT116 Cells , Heterografts , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Mitochondria/metabolism , Neoplasms/genetics , Neoplasms/pathology , PC-3 Cells , RNA, Messenger/genetics , RNA, Messenger/metabolism , Reactive Oxygen Species/metabolismABSTRACT
To investigate the modification of cell wall polysaccharides in relation to aril breakdown in harvested longan fruit, three pectin fractions (WSP, water soluble pectin; CSP, CDTA-soluble pectin; ASP, alkali soluble pectin) and one hemicellulose fraction (4 M KOH-SHC, 4 M KOH-soluble hemicellulose) were extracted, and their contents, monosaccharide compositions and molecular weights were evaluated. As aril breakdown intensified, CSP content increased while ASP and 4 M KOH-SHC contents decreased, suggesting the solubilization and conversion of cell wall components. Furthermore, the molar percentage of arabinose (Ara), as the main component of the side-chains, decreased largely in CSP and ASP while that of rhamnose (Rha), as branch point for the attachment of neutral sugar side chains, increased during aril breakdown. Analysis of (Ara+Gal)/Rha ratio showed that the depolymerization of CSP and ASP happened predominantly in side-chains formed of Ara residues. For 4 M KOH-SHC, more backbones were depolymerized during aril breakdown. Moreover, it was found that the molecular weights of CSP, ASP and 4 M KOH-SHC polysaccharides tended to decrease as aril breakdown intensified. These results suggest that both enhanced depolymerization and structural modifications of polysaccharides in the CSP, ASP and 4 M KOH-SHC fractions might be responsible for aril breakdown of harvested longan fruit.
Subject(s)
Pectins/chemistry , Polysaccharides/chemistry , Sapindaceae/metabolism , Cell Wall/chemistry , Chromatography, Gel , Fruit/metabolism , Hydroxides/chemistry , Molecular Weight , Monosaccharides/analysis , Pectins/metabolism , Polysaccharides/metabolism , Potassium Compounds/chemistry , Water/chemistryABSTRACT
Our group has shown that the polysaccharides extracted from Lycium barbarum (LBP) are neuroprotective for retinal ganglion cells (RGCs) in different animal models. Protecting RGCs from secondary degeneration is a promising direction for therapy in glaucoma management. The complete optic nerve transection (CONT) model can be used to study primary degeneration of RGCs, while the partial optic nerve transection (PONT) model can be used to study secondary degeneration of RGCs because primary degeneration of RGCs and secondary degeneration can be separated in location in the same retina in this model; in other situations, these types of degeneration can be difficult to distinguish. In order to examine which kind of degeneration LBP could delay, both CONT and PONT models were used in this study. Rats were fed with LBP or vehicle daily from 7 days before surgery until sacrifice at different time-points and the surviving numbers of RGCs were evaluated. The expression of several proteins related to inflammation, oxidative stress, and the c-jun N-terminal kinase (JNK) pathways were detected with Western-blot analysis. LBP did not delay primary degeneration of RGCs after either CONT or PONT, but it did delay secondary degeneration of RGCs after PONT. We found that LBP appeared to exert these protective effects by inhibiting oxidative stress and the JNK/c-jun pathway and by transiently increasing production of insulin-like growth factor-1 (IGF-1). This study suggests that LBP can delay secondary degeneration of RGCs and this effect may be linked to inhibition of oxidative stress and the JNK/c-jun pathway in the retina.