학술논문

Dietary Melatonin and Glycine Decrease Tumor Growth through Antiangiogenic Activity in Experimental Colorectal Liver Metastasis
Document Type
Academic Journal
Source
Nutrients. June, 2021, Vol. 13 Issue 6
Subject
Company growth
Oncology, Experimental -- Growth -- Statistics
Immunohistochemistry -- Statistics
Antineoplastic agents -- Statistics
Metastasis -- Statistics
Melatonin -- Statistics
Colorectal cancer -- Statistics
Glycine -- Statistics
Chemotherapy -- Statistics
Liver cancer -- Statistics
Cancer -- Chemotherapy -- Research
Antimitotic agents -- Statistics
Language
English
ISSN
2072-6643
Abstract
Despite multimodal treatment strategies, clinical outcomes of advanced stage colorectal cancer (CRC) patients remain poor. Neoadjuvant/adjuvant chemotherapy efficacy is limited due to chemoresistance, toxicity, and negative side effects. Since both melatonin and glycine have anti-cancer activities without relevant side effects, this study was designed to investigate their combined effects in experimental CRC liver metastases. CRC metastasis with CC531 cells were induced in male Wistar rats. Melatonin and glycine alone or their combination were supplemented for 14 days (n = 100). Blood parameters, a micro-computed tomography scan (tumor volume over time), and immunohistochemistry for Ki67 and CD31 expression in tumor tissue were compared between groups. Melatonin and glycine alone significantly reduced the tumor volume by 63.2% (p = 0.002) and 43% (p = 0.044) over time, respectively, while tumor volume increased by 8.7% in the controls. Moreover, treatment with melatonin and glycine alone reduced the tumor proliferation index. Most interestingly, the combination therapy did not have any influence on the above-mentioned tumor parameters. The leukocyte count was significantly increased with melatonin at the end of the experiment (p = 0.012) which was due to a high lymphocytes count. Tumor microvascular density was significantly reduced in all treatment groups. The results of this study suggest an inhibitory function for melatonin and glycine alone in the case of CRC liver metastasis growth by acting as natural antiangiogenic molecules, followed by angiogenesis-dependent cancer proliferation and immunomodulation.
Author(s): Mindaugas Kvietkauskas [1,2]; Viktorija Zitkute [1,2]; Bettina Leber [1]; Kestutis Strupas [2]; Philipp Stiegler (corresponding author) [1,*]; Peter Schemmer [1] 1. Introduction Colorectal cancer (CRC) is the third most [...]