The total test approach to standardization of immunohistochemistry

miR-223 increases gallbladder cancer cell sensitivity to docetaxel by downregulating STMN1

Background

MicroRNAs (miRs) are involved in cancer carcinogenesis, and certain regulatory miRs could provide promising therapeutic methods for refractory malignancies, such as gallbladder cancer (GBC). miR-223 was found to play a pivotal role in enhancing chemotherapeutic effects, therefore evoking interest in the role of miR-223 in GBC.

Results

miR-223 was decreased in GBC tissues and cell lines, and ectopic miR- 223 expression exhibited multiple anti-tumorigenic effects in GBC cells, including decreased proliferation, migration and invasion in vitro. However, treatment with a miR-223 inhibitor increased cell viability. We determined that STMN1 was negatively correlated with and regulated by miR-223 in GBC. miR-223 increased GBC sensitivity to docetaxel in vitro and in vivo, and the induced sensitivity to docetaxel was suppressed by the restoration of STMN1 expression.

Methods

We examined miR-223 expression in GBC tissue and GBC cell lines using qRT-PCR. The effects of modulated miR-223 expression in GBC cells were assayed using Cell Counting Kit-8 (CCK8), flow cytometry, and wound-healing and invasion assays. Susceptibility to docetaxel was evaluated in miR-223/STMN1-modulated GBC cells and xenograft tumor models. The protein expression of relevant genes was examined by Western blotting.

Conclusions

These findings indicated that miR-223 might serve as an onco-suppressor that enhances susceptibility to docetaxel by downregulating STMN1 in GBC, highlighting its promising therapeutic value.

Up-regulation of PKM2 promote malignancy and related to adverse prognostic risk factor in human gallbladder cancer

Recently, pyruvate kinase M2 (PKM2) has been implicated in the progression of certain cancers and might play pivotal roles in the formation of malignancy. However, the role of PKM2 in gallbladder cancer had not been well investigated. This study analyzed associations between PKM2 expression status with various clinical and pathologic parameters in a large cohort of gallbladder cancer (GBC) patients from a long term follow up results. The expression level of pyruvate kinase isotypes in GBC tissues and their adjacent normal gallbladder tissues were estimated by qRT-PCR and Western blot. PKM2 mRNA level were significantly high in gallbladder cancer tissues than in adjacent noncancerous tissues (P < 0.001). High expression of the PKM2 was detected in 55.71% paraffin-embedded GBC tissue. The high PKM2 expression was independently associated with poorer overall survival in patients with GBC (median survival 11.9 vs 30.1 months; hazard ratio 2.79; 95% CI = 1.18 to 6.55; P = 0.02). These findings indicated elevated expression of PKM2 is a prognostic factor for poor GBC clinical outcomes, implied involving of PKM2 in GBC progression.