RNAi­mediated downregulation of asparaginase­like protein 1 inhibits growth and promotes apoptosis of human cervical cancer line SiHa.

Asparaginase like 1 (ASRGL1) protein belongs to the N­terminal nucleophile group, cleaving the isoaspartyl­dipeptides and L­asparagine by adding water. It tends to be overexpressed in cancerous tumors including ovarian cancer and breast tumors. The present study assessed the potential ability of ASRGL1 as a molecular target in gene­based cervical cancer treatment. The protein expression level of ASRGL1 was determined in paraffin­embedded tumor specimen by immunohistochemistry. Additionally, in order to assess the activity of ASRGL1 during the process of cervical cancer cell multiplication, ASRGL1­short hairpin (sh) RNA­expressing lentivirus was established, which was used to infect SiHa cells. The Cellomics ArrayScan VT1 Reader identified the influence of downregulation on SiHa caused by RNA interference­intervened ASRGL1. Flow cytometric analysis was also performed to evaluate the influence. The cyclin dependent kinase (CDK2), cyclin A2, B­cell lymphoma 2 (Bcl­2) and Bcl­2­associated X protein (Bax) expression levels were assessed by western blot analysis. ASRGL1 was observed to be overexpressed in cervical cancer tissues when compared with the adjacent normal tissues. The knockdown of ASRGL1 in SiHa by ASRGL1­shRNA lentivirus infection significantly inhibited cell growth and enhanced cellular apoptosis; the cells were also captured during the S phase. The knockdown of ASRGL1 expression led to the increased expression of Bax and decreased expression of Bcl­2, CDK2 and cyclin A2. In conclusion, ASRGL1 was closely associated with growth and apoptosis in cervical cancer. Therefore, ASRGL1 may be a novel, potentially effective anti­cervical cancer therapy.

[Expression of nucleostemin mRNA and protein in the esophageal squamous cell carcinoma].

OBJECTIVE: To investigate the mRNA and protein expression of nucleostemin (NS) in human esophageal squamous cell carcinoma. METHODS: The mRNA and protein expression of NS were detected in 31 mucosal atypical hyperplasia specimens, 62 esophageal squamous cell carcinoma specimens and the matched normal esophageal mucosa samples by RT-PCR and immunohistochemistry method, respectively. RESULTS: The positive expression rate of NS protein in normal esophageal mucosa, atypical hyperplasia and esophageal squamous cell carcinoma was 17.7% (11/62), 41.9% (13/31) and 69.4% (43/62), respectively. There was a significant difference among the above three groups (chi2 = 33.676, P < 0.01). The expression levels of NS mRNA in esophageal squamous cell carcinoma (0.971 +/- 0.121) was significantly higher than that in the atypical hyperplasia (0.913 +/- 0.085) and also in the normal esophageal mucosa (0.866 +/- 0.103; F = 14.829, P < 0.01). The expression level of both NS protein and mRNA was positively correlated with histological grade, infiltration depth, and lymph node metastasis (P < 0.05), but not with age, gender or pathological type (P > 0.05). CONCLUSION: Our results indicate that nucleostemin mRNA and protein are over-expressed in human esophageal squamous cell carcinoma, and it may be related with its oncogenesis.