Upregulation of micro-ribonucleic acid-128 cooperating with downregulation of PTEN confers metastatic potential and unfavorable prognosis in patients with primary osteosarcoma.

OBJECTIVE: Abnormal expression of micro-ribonucleic acid (miRNA [miR])-128 has been observed in various human cancer types, and its validated target genes are implicated in cancer-related cellular processes, such as cell proliferation, differentiation, and apoptosis. Especially, it has been demonstrated that miR-128 may play an important role in the proliferation of human osteosarcoma cells in vitro by directly inhibiting PTEN, which functions as a tumor suppressor in this malignancy. In the current study, we investigated the involvement of miR-128 and its target gene PTEN in tumor progression and prognosis in patients with primary osteosarcoma. MATERIALS AND METHODS: Expression levels of miR-128 and PTEN messenger RNA in osteosarcoma and noncancerous bone tissues obtained from 100 patients with primary osteosarcoma were detected by quantitative real-time polymerase chain reaction. RESULTS: Expression levels of miR-128 and PTEN messenger RNA in osteosarcoma tissues were significantly higher and lower, respectively, than those in noncancerous bone tissues (both P<0.001). In addition, high miR-128 expression and low PTEN expression, alone (miR-128-high or PTEN-low) or combined (miR-128-high/PTEN-low), were all dramatically associated with poor response to chemotherapy and positive metastasis. More importantly, the associations of miR-128-high/PTEN-low expression with these clinicopathological parameters were more significant than miR-128-high or PTEN-low alone. Finally, miR-128 expression, PTEN expression, miR-128/PTEN expression, the response to chemotherapy and the metastatic status were all identified as independent prognostic factors for overall survival and disease-free survival. CONCLUSION: These findings indicate for the first time that the deregulation of miR-128 and its target gene PTEN may be involved in the aggressive progression of human osteosarcoma. Notably, the upregulation of miR-128 cooperating with the downregulation of PTEN may confer an unfavorable prognosis in patients with this malignancy.

Molecular characteristics of MDR Mycobacterium tuberculosis strains isolated in Fujian, China.

Of 75 MDR isolates from Fujian Province, the sensitivity of RIF, INH, EMB, SM, OFLX and KAN resistance by DNA sequencing was 96.0%, 96.0%, 66.7%, 66.0%, 84.2% and 75.0%, respectively. We also identified that minority mutations in the mixed Mycobacterium tuberculosis population may be responsible for two "false-negative" results. In addition, Beijing genotype is still the predominant sublineage in the MDR TB cases from Fujian.

[Preliminary study on the MLVA genotyping of Mycobacterium tuberculosis isolates in Fujian province].

OBJECTIVE: To preliminarily understand the genotyping characteristics regarding the variable number tandem repeats (VNTR) of Mycobacterium tuberculosis clinical isolates so as to provide evidence for the development of tuberculosis control and prevention programs in Fujian province. METHODS: Fifteen VNTR locus sets were used to detect the clinical isolates from the fifth surveillance project on tuberculosis resistance, in Fujian province. BioNumerics version 4.5 were used to analyze the cluster from the results generated by genotyping. RESULTS: 313 Mycobacterium tuberculosis isolates were divided into 9 clusters, including I, II, III, IV, V, VI, VII, VIII and IX, with the number of 220, 9, 48, 2, 1, 3, 10, 10, 10 isolates, respectively. Cluster I was the major lineage, accounting for 70.3% (220/313) of the total. Resistance rates of cluster I isolates to isoniazid, streptomycin, ethambutol and multi-drug-resistant were not statistically different from other clusters (P > 0.05). However, resistance rate to rifampicin (RFP) was significantly higher than that of other isolates of the clusters, 33.2% (73/220) vs. 20.4% (19/93) (P < 0.05). CONCLUSION: The strains isolated from Fujian province showed significant polymorphism on genotyping. Cluster I seemed to be the dominant, calling for the close monitoring program on cluster I strains. RESULTS: from our initial studies demonstrated the existence of significant correlation between cluster I strains and drug resistance to RFP.