Decreased blood riboflavin levels are correlated with defective expression of RFT2 gene in gastric cancer.
OBJECTIVE
To investigate the relationship between blood riboflavin levels and riboflavin transporter 2 (RFT2) gene expression in gastric carcinoma (GC) development.


METHODS
High-performance liquid chromatography was used to detect blood riboflavin levels in patients with GC. Real-time fluorogenic quantitative polymerase chain reaction and immunohistochemistry were used to analyze the expression of RFT2 mRNA and protein in samples from 60 GC patients consisting of both tumor and normal tissue.


RESULTS
A significant decrease in the RFT2 mRNA levels was detected in GC samples compared with those in the normal mucous membrane (0.398 ± 0.149 vs 1.479 ± 0.587; P = 0.040). Tumors exhibited low RFT2 protein expression (75%, 16.7%, 8.3% and 0% for no RFT2 staining, weak staining, medium staining and strong staining, respectively), which was significantly lower than that in the normal mucous membrane (10%, 16.7%, 26.7% and 46.7% for no RFT2 staining, weak staining, medium staining and strong staining, respectively; P < 0.05). Tumors with low RFT2 expression were significantly associated with tumor stage and histological grade. Moreover, a significantly decrease in Uyghur patients was observed compared with Han patients. However, other parameters-gender, tumor location and lymph node metastasis-showed no significant relationship with RFT2 expression. Blood riboflavin levels were reverse correlated with development of GC (1.2000 ± 0.97569 ng/mL in high tumor stage patients vs 2.5980 ± 1.31129 ng/mL in low tumor stage patients; P < 0.05). A positive correlation of plasma riboflavin levels with defective expression of RFT2 protein was found in GC patients (χ² = 2.619; P = 0.019).


CONCLUSIONS
Defective expression of RFT2 is associated with the development of GC and this may represent a mechanism underlying the decreased plasma riboflavin levels in GC.
Department of Oncology, the First Affiliated Hospital, Medical University of Xinjiang, Urumqi 830054, Xinjiang Uygur Autonomous Region, China.
Maynur
M
Eli
De-Sheng
DS
Li
Wei-Wei
WW
Zhang
Bing
B
Kong
Chen-Song
CS
Du
Maimaitiaili
M
Wumar
Batur
B
Mamtimin
Ilyar
I
Sheyhidin
Ayshamgul
A
Hasim
D000328:Adult; D000368:Aged; D044466:Asian People; D002454:Cell Differentiation; D016009:Chi-Square Distribution; D002681:China / Q000453:epidemiology; D002851:Chromatography, High Pressure Liquid; D015536:Down-Regulation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008207:Lymphatic Metastasis; D008297:Male; D026901:Membrane Transport Proteins / Q000032:analysis* / Q000235:genetics; D008875:Middle Aged; D009367:Neoplasm Staging; D012333:RNA, Messenger / Q000032:analysis; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012256:Riboflavin / Q000097:blood*; D013274:Stomach Neoplasms / Q000097:blood / Q000737:chemistry* / Q000208:ethnology / Q000235:genetics / Q000473:pathology
D026901:Membrane Transport Proteins; D012333:RNA, Messenger; C548553:SLC52A3 protein, human; D012256:Riboflavin