Correlation of human epidermal growth factor receptor protein expression and colorectal cancer

AIM:To investigate the correlation between human epidermal growth factor receptor(HER-2) protein expression and colorectal cancer(CRC) using a casecontrol study and meta-analysis.METHODS:Tumor tissue specimens from 162 CRC patients were selected for the case group.Fifty cases were randomly selected,and normal CRC tissue at least 10 cm away from the tumor margins of these cases was used to generate the control group.The expression of the HER-2 protein in the 162 CRC tissue samples and the 50 adjacent normal mucosa tissue samples was detected via immunohistochemistry.The experimental data were analyzed using SPSS 18.0software,and R software version 3.1.0 was utilized for further verification.RESULTS:The expression of HER-2 protein in the 162 CRC tissue samples was significantly higher than in the normal tissue specimens.The data showed that the expression of HER-2 in CRC was related to the Dukes' stage,the depth of invasion and lymph node metastasis.The HER-2-positive patients had lower 3-and 5-year OS rates than the HER-2-negative patients,but there was no significant difference.However,there was a statistically significant difference in the 3- and5-year disease-free survival(DFS) rates of HER-2-positive and HER-2-negative patients.The results of the meta-analysis showed that the expression of HER-2in CRC patients was statistically significantly increased over that of healthy people.The 3-year DFS rate in HER-2-positive patients was markedly lower than that in HER-2-negative patients.CONCLUSION:Down-regulation of HER-2 expression might be a dependable strategy for CRC therapy.

OsCAND1 Is Required for Crown Root Emergence in Rice

Crown roots are main components of the fibrous root system and important for crops to anchor and absorb water and nutrition. To understand the molecular mechanisms of crown root formation, we isolated a rice mutant defective in crown root emergence designated as Oscand1 （named after the Arabidopsis homologous gene AtCAND1）. The defect of visible crown root in the Oscandl mutant is the result of cessation of the G2/M cell cycle transition in the crown root meristem. Map-based cloning revealed that OsCAND1 is a homolog ofArabidopsis CAND1. During crown root primordium development, the expression of OsCAND1 is confined to the root cap after the establishment of fundamental organization. The transgenic plants harboring DRS：：GUS showed that auxin signaling in crown root tip is abnormal in the mutant. Exogenous auxin application can partially rescue the defect of crown root development in Oscandl. Taken together, these data show that O5CAND1 is involved in auxin signaling to maintain the G2/M cell cycle transition in crown root meristem and, consequently, the emergence of crown root. Our findings provide new information about the molecular regulation of the emergence of crown root in rice.