Rabbit Anti-ADRB2 monoclonal antibody, clone KN213-17

Epidemiological data show that chronic stress has adverse effects on the incidence and progression of cancer. As a critical target organ for stress hormones, the stomach is frequently subjected to stress-related injury. However, few reports regarding the association between stress and gastric cancer (GC) have been published. The present study aimed to investigate the effect of chronic stress on the growth and survival of GC, and the role of the autophagy process. A restraint-stress procedure over 21 days was used to establish a chronic stress mouse model. Subcutaneous xenografts and gastric orthotopic xenografts were established in BALB/c nude mice. Alzet osmotic minipumps containing either PBS or propranolol hydrochloride was inserted on the nape of the neck 7 days prior to the initiation of restraint stress. The presence of autophagosomes and autolysosomes were examined by electron microscopy. The stress hormone norepinephrine significantly enhanced the proliferation of GC cells. By inhibiting adrenoreceptor expression, it was demonstrated that 2-adrenergic receptor (ADRB2) was the specific -adrenergic receptor subtype responsible for catecholamine release. In addition, it was demonstrated that the induction of autophagy was a novel consequence of 2-adrenergic activation in GC cells. This was demonstrated by the appearance of double-membrane vesicles, punctuate GFP-RFP-microtubule-associated protein 1 light chain 3 distribution in the cytoplasm and a corresponding increase in autophagic flux. Notably, norepinephrine-induced autophagy was shown to have a tumor-promoting role under conditions of chronic stress in vitro and in vivo. It was further demonstrated that, upon activation of cAMP-response element binding protein, chronic stress promoted autophagic flux through the adenosine 5-monophosphate-activated protein kinase-unc-51 like autophagy activating kinase 1 (AMPK-ULK1) pathway. Tissue microarray analysis revealed a negative correlation between the expression of ADRB2 and autophagic marker p62/sequestosome-1 in GC tumor samples. Additionally, high protein levels of ADRB2 correlated positively with tumor, node, metastasis stage and poor prognosis in patients with GC. These results establish a novel pathway that chronic stress activates tumor-promoting autophagy to accelerate the progression of GC. The present study is the first, to the best of our knowledge, providing preclinical evidence that chronic stress serves a role in the progression of GC.

Background and Study Aim: Many wrestlers undergo extreme dieting, with rapid weight loss and fluid restriction, to achieve rule weight as measured before a match. Insight into the genetics of weight loss has been gained from studies of patients with lifestyle-related diseases, including obesity and diabetes, who show weight loss resistance in the face of therapeutic interventions such as diet and exercise. However, the effect of single nucleotide polymorphisms (SNPs) in obesity-related genes on the rapid weight loss that athletes experience in weight-class sports such as wrestling remains to be elucidated. The purpose of this study was the effect of SNPs in ADRB3, ADRB2, and UCP1 on rapid weight loss in female wrestlers. Material and Methods: Twenty-two female wrestlers who sought weight loss before a match participated in this study. We performed real-time polymerase chain reaction using a quenching probe to determine subject genotypes. Results: Thirteen subjects had the ADRB3 (Trp/Trp) wild-type genotype, whereas 9 had the ADRB3 (Trp/Arg) polymorphic genotype. Five subjects had the ADRB2 (Arg/Arg) genotype, and 17 had the ADRB2 (Arg/Gly) polymorphic genotype. Five subjects had the UCP1 (-3826A/A) genotype, and 17 had the UCP1 (-3829A/G) polymorphic genotype. No statistically significant associations were detected between genotypes of obesity-related genes with any of the weight loss indicators measured. Conclusions: SNPs in the obesity-related genes ADRB3, ADRB2, and UCP1 do not appear to affect weight loss in female wrestlers during rapid weight loss regimens prior to a match.