RESUMEN
AIMS: TWIST protein has been implicated in neoplastic transformation and development of some cancers. In this study, we aimed to investigate the expression of TWIST in gastric cancer and its clinical significance. METHODS: A total of 76 cases of archival gastric cancer tissues were immunohistochemically evaluated for TWIST expression, and its expression was correlated with clinicopathological parameters. Semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) was used to detect the mRNA of TWIST in four gastric cancer cell lines and a normal immortalised gastric epithelial cell line (GES-1). The expression of TWIST protein in these cell lines and 14 pairs of fresh gastric carcinoma and adjacent normal tissue samples was detected by Western blotting. RESULTS: TWIST expression increased in diffuse-type gastric carcinoma compared with intestinal-type gastric carcinoma (26/42, 61.9% versus 9/34, 26.5%, p<0.05). TWIST expression was significantly increased in 35 (46.1%) of the 76 cancers and correlated with lymph node metastasis (node positive rate 60.4%; node negative rate 21.4%; p<0.05). The expression of TWIST protein was higher in 9/14 (64.3%) fresh cancer tissues compared with adjacent normal tissues. The expression of mRNA and protein of TWIST in gastric cancer cell lines was up-regulated compared with that in GES-1. CONCLUSIONS: TWIST was highly expressed in gastric cancer. Its up-regulation was associated with the neoplastic transformation and subsequent development of gastric cancer. Therefore, TWIST may be a useful prognostic marker and target for gastric cancer therapy.
Asunto(s)
Adenocarcinoma/metabolismo , Transformación Celular Neoplásica/metabolismo , Proteínas Nucleares/biosíntesis , Lesiones Precancerosas/metabolismo , Neoplasias Gástricas/metabolismo , Proteína 1 Relacionada con Twist/biosíntesis , Adenocarcinoma/patología , Western Blotting , Línea Celular Tumoral , Femenino , Humanos , Inmunohistoquímica , Masculino , Metaplasia/metabolismo , Persona de Mediana Edad , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Gástricas/patología , Regulación hacia ArribaRESUMEN
<p><b>OBJECTIVE</b>To investigate the binding effect of the short peptide SY1 to the multidrug-resistant gastric cancer cell line SGC7901/VCR cells and its reversing effect on those cancer cells.</p><p><b>METHODS</b>The cultured cells were divided into two groups named SGC7901 and SGC7901/VCR. The SGC7901/VCR group was co-cultured with vincristine (VCR). SY1 was obtained from cyclic 7-mer peptide library by differential screening. Immunofluorescence technique was used to detect the capacity of SY1-containing positive phage specifically binding to SGC7901/VCR cells, compared with that of the negative phage and unrelated phage. MTT assay in vitro was performed to analyze the alteration of drug resistance of SGC7901/ VCR cells, using the positive phages and the chemically synthesized SY1 peptide. Flow cytometry assay was performed to detect the accumulation and retention of adriamycin (ADM) in the SGC7901/VCR cells.</p><p><b>RESULTS</b>Immunofluorescence analysis showed that the SY1-containing positive phages could bind to the SGC7901/VCR cell surface but not to its parent cell line SGC7901 cells. The unrelated phage and negative phage did not bind to SGC7901/VCR cells. These results indicated that SY1 could specifically bind to SGC7901/VCR cells. MTT assay in vitro showed that the survival rate of SGC7901/VCR cells was reduced considerably by the positive phages and the chemically synthesized SY1 peptide (P <0. 05), indicating that SY1 enhanced the sensitivity of SGC7901/VCR cells to chemotherapeutic drug VCR. Flow-cytometric detection showed that SY1 enhanced the accumulation of ADM in the SGC7901/VCR cells, compared with that of the negative phages and the unrelated phages (P <0.05).</p><p><b>CONCLUSION</b>SY1 not only is able to bind to SGC7901/VCR cells specifically, but also can partly reverse the resistance of SGC7901/VCR cell line to chemotherapeutic drug VCR. Those findings might be important to open a new approach to reverse the gastric cancer MDR.</p>