RESUMO
Background & objectives: ING3 (inhibitor of growth protein 3) overexpression decreased S-phase cell population and colony-forming efficiency, and induced apoptosis at a p53-mediated manner. The aim of this study was to investigate the clinicopathological and prognostic significance of ING3 expression in colorectal carcinogenesis and subsequent progression. Methods: ING3 expression was examined by immunohistochemistry on tissue microarray containing colorectal non-neoplastic mucosa (NNM), adenoma and adenocarcinoma. Colorectal carcinoma tissue and cell lines were studied for ING3 expression by Western blot or RT-PCR. Results: ING3 mRNA was differentially expressed in Colo201, Colo205, DLD-1, HCT-15, HCT-116, HT-29, KM-12, SW480, SW620 and WiDr cells. Carcinomas showed significantly lower ING3 expression than matched NNM at mRNA level (P<0.05), but not at protein level. Immunohistochemically, ING3 expression was significantly decreased from NNM, adenoma to adenocarcinoma (P<0.05). ING3 expression was not correlated with age, sex, tumour size, depth of invasion, lymphatic or venous invasion, lymph node metastasis, tumour- node- metastasis staging or differentiation. Kaplan-Meier analysis indicated that ING3 protein expression was not associated the prognosis of the patients with colorectal carcinoma (P<0.05). Interpretation & conclusions: Our study showed that downregulated ING3 expression might play an important role in colorectal adenoma-adenocarcinoma sequence. Further studies are required to understand the mechanism.
RESUMO
Background & objective: Gastric cancer is the fourth most common cancer and the second leading cause of cancer-related deaths after lung carcinoma. The aim of this study was to understand the difference in clinicopathological behaviours and prognosis of gastric cancer in patients from China and Japan. Methods: Paraffin-fixed tissue samples of gastric cancer were collected retrospectively from two hospitals between 1993 to 2006 in Japan (n=2063) and during 1980-2003 in China (n=2496) respectively, and staging was done by TNM system and typing by Japanese Endoscopy Society criteria or Borrmann’s classification. The histological architecture of the tumours was expressed according to Lauren’s classification. Results: Compared to Japan, the occurrence of gastric cancer was more common in younger Chinese population and prone to invasion and metastasis in muscularis propia, lymphatic, lymph node, liver, peritoneal parts, and exhibited large tumour size and high TNM staging in both the sexes and in different age groups (P<0.05). Intestinal and mixed types of carcinomas were more frequently observed in Japanese patients compared to Chinese and the difference was significant (P<0.05). It was observed that the commonly reported types in early gastric cancers (EGC) in Japanese patients were IIc, IIa+IIc or IIa while those of Chinese patients were IIc, III or IIb. In the case of advanced gastric cancers (AGC), type II and III were most common in both the countries. The cumulative survival rate of Chinese patients was significantly (P<0.05) higher compared to Japanese in different stratified groups via depth of invasion, TNM staging or Lauren’s classification. Interpretation & conclusion: Gastric cancers in Chinese patients had more aggressive pathological characteristics and poorer prognosis than those from Japan. To reduce incidence and to improve treatment facilities, it is necessary to have a systematic screening system.