Advances in Study on MicroRNAs and their Target Genes in Occurrence,Development and Treatment of Gastric Cancer / 胃肠病学

MicroRNAs( miRNAs)are a family of endogenous noncoding small RNA molecules that are approximately 20 nucleotides in length. Aberrant expression or dysfunction of miRNAs and subsequent dysregulation of their target genes might be involved in the occurrence and development of various cancers. Gastric cancer is a leading malignant disease worldwide. Recent studies have shown that some miRNAs are closely associated with the proliferation,migration,invasion, apoptosis and chemosensitivity of gastric cancer cells by regulating their target genes. Advances in study on gastric cancer-related miRNAs,their target genes,and the use of miRNAs-targeted therapy in gastric cancer were reviewed in this article.

Influence of 17AAG on proliferation and invasion of gastric cancer cell and its mechanism / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the effect of 17-allylamino-demethoxygeldanamycin (17AAG) on the proliferative and invasive ability of gastric cancer cells and associated mechanism.</p><p><b>METHODS</b>The proliferative ability was tested by MTT method and the cell cycle was detected by flow cytometry(FCM) when 17AAG was used to treat gastric cancer cell SGC7901. Apoptosis was detected by FCM and PI-Annexin V double staining. The invasive ability was tested by transwell method. Expression of HSP90, HSP70, c-met and AKT was detected by Western blot.</p><p><b>RESULTS</b>The growth of SGC7901 cells was inhibited after the administration of 17AAG, and the inhibitation was dose- and time-dependent. The cell cycle was blocked at the G0/G1 phase. The apoptotic ratio in 17AAG group was much higher than that in blank group and DMSO group (P<0.01). The cellular invasive ability decreased significantly (P<0.01). The expression of HSP70 was elevated by 17AAG, and the expression of c-met and AKT was down-regulated, but no change of HSP90 was observed.</p><p><b>CONCLUSION</b>17AAG can inhibit the proliferative and invasive ability of SGC7901 cells, and induces apoptosis through down-regulating the expression of HSP90 client proteins instead of the target HSP90 itself.</p>

Five Cases Report of Solid Tumor Synchronously with Hematologic Malignancy / Journal of the Korean Cancer Association, 대한암학회지

The reported incidence of synchronous multiple primary cancer (SMPC) is rare, and it is even less common to observe synchronous solid tumor with a hematological malignancy. We report five cases of solid tumor presented synchronously with hematological malignancy, all observed within a 2 year period at the oncology department of a university hospital in Shanghai, China. These individual cases included lung adenocarcinoma with chronic myelogenous leukemia, colon cancer with solitary plasmocytoma, gastric adenocarcinoma with diffuse large B cell non-Hodgkin's lymphoma, lung adenocarcinoma with multiple myeloma, and colon cancer with diffuse large B cell non-Hodgkin's lymphoma. It is challenging to therapeutically control the biological behavior of concurrent multiple primary tumors, and there is no standard treatment for such rare conditions. In this paper we discuss these five cases of SMPC and their treatments.

K-ras status and efficacy of cetuximab-containing regimen in the treatment of patients with metastatic colorectal cancer / 中国癌症杂志

Background and purpose: Cetuximab-containing regimen has been increasingly applied in the treatment of patients with metastatic colorectal cancer. Simultaneously, the predictive factors of outcome for cetuximab have been thoroughly researched. The aim of this study was to evaluate the relationship between K-ras status and efficacy of cetuximab containing regimen in the treatment of patients with metastatic eolorectal cancer. Methods: Between March 2006 and June 2008, twenty-seven patients with metastatic colorectal cancer were treated with cetuximab in combination with chemotherapy. The K-ras mutation status [wild-type (wt) or mutation (nat)] was examined by polymerase chain reaction (PCR) and direct sequencing. The influence of K-ras mutation status on efficacy of cetuximab-containing regimen was analyzed. Results: For 27 patiants in this cohort, K-ras wt was detected in 55.6% (15/27) cases and K-ras mt in 44.4% (12/27) cases. Statistically significant differences were found between the patients with K-ras wt and K-ras mt in terms of overall response rate (ORR) (66.7% vs 25.0%,P=0.035) and progression-free survival (PFS) (8 months vs 4 months, P=0.0028). However, there was no significant difference in overall survival (OS) (19 months vs 12 months, P>0.05). The most common treatment-related adverse effect was skin reaction, with incidence rate of 80.0% and 66.7% (P>0.05), respectively. No treatment related death was observed. Conclusion: K-ras mutation status is a predictive factor of good efficacy of cetuximab-containing regimen in the treatment of patients with metastatic colorectal cancer. Patients with K-ras wt could benefit from cetuximab in combination with chemotherapy.

Down-regulation of osteopontin by siRNA on the biological behavior of gastric cancer cell lines / 中华消化杂志

Objective To explore the effects of down regulation of osteopontin(OPN)on the bio- logical behavior of MKN28 and SGC7901 cell lines.Methods OPN siRNA was designed according to the relevant literature and was transfected into the two cell lines.Fluorescent labeling was used to test the transfected efficiency.The down-regulation of OPN protein was measured by Western blot.Real- time PCR was used to test the ratio and time difference of down-regulation of OPN mRNA after siRNA transfection.The biological changes before and after OPN siRNA transfected into these two cell lines were tested by flow cytometry(to test cell cycle and apoptosis)and MTT method(to test the prolifera- tion for the consecutive seven days)and the difference between OPN siRNA transfected or non-transfect- ed cells was compared using mixed model.The capability of moving and invasion of cancer cells were tested by Transwell method and analyzed by t-test.Results The transfected efficiency of OPN siRNA were more than 90% in the two cell lines.OPN mRNA down-regulated to 47% at the 72th hour in SGC7901,while 40% at the 48th hour in MKN28.The expression of OPN protein was both down- regulated after siRNA transfection in the two cell lines.The proliferation decreased after transfected with OPN siRNA both in MKN28 andSGC7901(P