A potential role for interleukin-8 in the metastatic phenotype of breast carcinoma cells

This study shows a strong correlation between the metastatic potentials of breast carcinoma cell lines and their ectopic expression of interleukin-8 (IL-8). Correlations exist for both constitutive and induced levels of IL-8 released. A correlation was also observed between cell morphology, metastatic potential, and IL-8 profile. Metastatic lines are fusiform in appearance, whereas, nonmetastatic lines are epithelioid. The metastatic potential of two breast carcinoma lines was examined using an orthotopic model of spontaneous metastasis. Metastatic cells formed rapidly growing, poorly differentiated primary tumors that metastasized. Nonmetastatic cells formed rapidly growing differentiated primary tumors that did not produce detectable metastases. Comparison of IL-8 expression by the parental cells and cell cultures developed from primary and metastatic tumors, demonstrates that IL-8 released by cultured cells from the primary tumor is higher than that of the parental cells, and IL-8 released by cultured cells derived from the metastatic lung tumors is greater than that released by cultured cells derived from the primary tumor. These data demonstrate a strong correlation between the metastatic phenotype of a cell and its IL-8 expression, suggesting a role for IL-8 in promoting the metastatic potential of breast tumor cells.     

Expression of PRL-3 phosphatase in human gastric carcinomas: close correlation with invasion and metastasis.

OBJECTIVE: High expression of PRL-3, a protein tyrosine phosphatase, has been reported to be associated with metastasis of colorectal carcinoma. The aim of this study is to investigate the significance of PRL-3 expression in tumor progression and metastasis of gastric carcinoma. METHODS: The levels of PRL-3 mRNA expression in 8 gastric cancer cell lines were examined by RT-PCR. Ninety-four human gastric carcinomas and 54 matched lymph node metastases were employed in this study. The expression of PRL-3 was detected by immunohistochemistry and the relationship with clinicopathological parameters was analyzed. RESULTS: The expression of PRL-3 mRNA was clearly detected in 7 of 8 gastric cancer cell lines (87.5%) by RT-PCR. In tumor samples, PRL-3 expression was detected in 68% of primary gastric carcinoma (with nodal metastasis 81.5%, without nodal metastasis 50%; p = 0.004). The incidence of PRL-3 expression in lymph node metastasis was significantly higher than that in primary gastric cancers (p < 0.001). Moreover, PRL-3 expression was closely associated with lymphatic invasion (p = 0.002), extent of lymph node metastasis (p = 0.002) and tumor stage (p = 0.045). CONCLUSIONS: These results strongly suggest that PRL-3 expression may play a significant role in invasion and metastasis of gastric carcinoma. PRL-3 might be a novel molecular marker for aggressive gastric cancer.     

Reduced expression of the cell-cycle inhibitor p27Kip1 is associated with progression and lymph node metastasis of gastric carcinoma

AIMS: p27Kip1 (p27), a cyclin-dependent kinase inhibitor, plays an important role as inhibiting the progression of the cell cycle. Decreased expression of p27 is associated with high histological grade and aggressiveness of several human tumours. We aimed to evaluate the role of p27 in the progression and metastasis of gastric carcinoma. METHODS AND RESULTS: We analysed the expression of p27 in 67 primary gastric carcinomas and 31 lymph node metastases by immunohistochemistry. Reduced expression of p27 was found more frequently in advanced gastric cancer (40.9%) than in early gastric cancer (15.6%) (P < 0.001). Decreased p27 expression correlated with large tumour size, high histological grade, lymphatic invasion, advanced stage, deep invasion, lymph node metastasis and recurrence. The expression of p27 showed an inverse correlation with the Ki67 labelling index. There was a significant reduction of p27 expression in metastatic tumour cells in lymph nodes (mean positive cells: 3. 7%) when compared to the corresponding primary gastric carcinomas (mean positive cells: 8.1%) (P = 0.008). CONCLUSIONS: Alterations of p27 expression may play an important role in the progression and metastasis to lymph node of tumour cells in human gastric carcinoma.     

Heparanase expression correlates with invasion and poor prognosis in gastric cancers

Degradation of basement membrane and extracellular matrix structures are important features of the metastatic process of malignant tumors. Human heparanase degrades heparan sulfate proteoglycans, which represent the main components of basement membranes and the extracellular matrix. Because of the role of heparanase in tumor invasion and metastasis, we examined heparanase expression in primary gastric cancers and in cell lines derived from gastric cancers by immunohistochemistry and RT-PCR, respectively. Four of seven gastric cancer cell lines showed heparanase mRNA expression by RT-PCR. Heparanase protein was detected in both the cytoplasm and the nucleus of heparanase mRNA-positive cells by immunohistochemical staining. Heparanase expression was confirmed in 35 (79.5%) of 44 gastric tumor samples by immunohistochemical staining. However, no or weak heparanase expression was detected in normal gastric mucosa. In situ hybridization showed that the mRNA expression pattern of heparanase was similar to that of the protein, suggesting that increased expression of the heparanase protein at the invasive front was caused by an increase of heparanase mRNA in tumor cells. Analysis of the clinicopathologic features showed stronger heparanase expression in cases of huge growing tumors, extensive invasion to lymph vessels, and regional lymph node metastasis. In gastric cancer, patients with heparanase expression showed significantly poorer prognosis than those without such expression (p = 0.006). In conclusion, our findings suggest that high expression of heparanase in gastric cancer is a strong predictor of poor survival.     

Significance of dysadherin and E-cadherin expression in differentiated-type gastric carcinoma with submucosal invasion

Dysadherin is a cancer-associated cell membrane glycoprotein that down-regulates E-cadherin and plays important roles in tumor progression and metastasis. Differentiated-type gastric carcinoma can be classified into 2 histologic subtypes according to the presence of poorly differentiated components: a mixed type (differentiated carcinoma with poorly differentiated components) and a pure type (purely differentiated-type adenocarcinoma). We studied the clinicopathologic features of 318 cases of differentiated-type gastric carcinoma with submucosal invasion and evaluated the immunohistochemical expression of dysadherin and E-cadherin. We also evaluated 46 cases of metastatic lymph nodes. Tumors with combined dysadherin-positive (≥50%) expression and E-cadherin-negative (<50%) expression had significantly higher proportions of the moderately differentiated type, deeper submucosal invasion, positivity of lymphatic permeation, and positivity of lymph node metastasis than tumors with other combinations of dysadherin and E-cadherin expression (P = .0009, P = .0015, P = .0273, and P = .0187, respectively). Moreover, the frequency of dysadherin-positive (≥50%) expression was higher in the mixed type (60.3%) than in the pure type (12.4%) (P < .0001), whereas the frequency of E-cadherin-negative (<50%) expression was higher in the mixed type (84.5%) than in the pure type (50.5%) (P < .0001). The frequency of dysadherin expression in the metastatic lymph nodes (80.4%) was significantly higher than that in the primary tumors (45.7%) (P = .001). Dysadherin-positive (≥50%) expression and E-cadherin-negative (<50%) expression may be correlated with the mixed type. Combined dysadherin-positive (≥50%) expression and E-cadherin-negative (<50%) expression may be valuable information for predicting aggressive tumor behavior.     

RhoC is essential for the metastasis of gastric cancer

Rho family members are known to regulate malignant transformation and motility of cancer cells, but the clinicopathological significance of RhoC remains unclear yet in the case of gastric cancer. In this study, we evaluated the protein expression level of RhoC in gastric cancer tissues and cell lines. Results showed that only weak staining of RhoC was detected in 3 of 33 non-tumorous cases by immunohistochemistry. The expression of RhoC was significantly higher in gastric cancer tissues (23/42, 54.8%) than in non-tumorous tissues (p < 0.01). Further analysis demonstrated that RhoC had high specificity (80.0%) in detecting gastric carcinomas with metastatic potential. RhoC was positively expressed in 18 out of 20 metastases (90.0%), even higher than that in primary gastric cancer tissues. Western blot showed that RhoC was up-regulated in five different gastric cancer cell lines but not expressed in SV40-transformed immortal gastric epithelial cell GES-1. Overexpression of RhoC GTPase in GES-1 cells could produce the motile and invasive phenotype but did not alter the monolayer growth rate. To further study the functions of RhoC, we took the powerful siRNA technology to knock down the expression of RhoC in SGC7901 cells. It was shown that down-regulation of RhoC did not affect the proliferation of SGC7901 cells. However, interference of RhoC expression could inhibit migration, invasion, and anchorage-independent growth of SGC7901 cells. In conclusion, RhoC may play a very important role in the metastasis of gastric carcinoma. Therapeutic strategies targeting RhoC and RhoC-mediated pathways may be a novel approach for treating metastasis of gastric cancer.     

p53, p16 and RB expression in adenosquamous and squamous cell carcinomas of the stomach

The expression of p53, p16 and RB proteins and their clinicopathologic correlation were investigated in 15 cases of primary gastric adenosquamous carcinoma and 2 cases of squamous cell carcinoma of the stomach. The male to female ratio of the patients was 13:4 and the average age was 55.7 years. None of the cases was early gastric carcinoma, and none of the adenocarcinoma components were of the diffuse or signet ring cell types. Fourteen cases showed metastasis to regional lymph nodes and/or other organs at the time of surgery. The adenocarcinoma component was metastasized to lymph nodes in 12 cases, and both adenocarcinoma and squamous cell carcinoma components were metastasized in three cases. The altered expression of p53 correlated with the advanced stage, but did not correlate with the depth of invasion, lymph node metastasis or recurrence. The altered expression of p16 and RB proteins did not correlate with any of the above clinico-pathologic factors. Both the adenocarcinoma and squamous cell carcinoma components revealed an inverse correlation between the expression pattern of p16 and RB proteins (p < 0.05). This suggests that the two proteins share a role in the carcinogenesis of these tumors. The expression pattern of p53 proteins in the adenocarcinoma and squamous cell carcinoma components was exactly the same in all of the cases. The expression patterns of p16 and RB protein were also identical in most of the cases. The expression patterns of all three proteins in the metastatic lesions were also identical to those in the primary lesions. The fact that the alteration of the three tumor suppressor gene products shares the same pattern suggests that squamous and adenocarcinoma components in the stomach originate from the same or a genetically related clone.     

Ovarian clear cell carcinomas: RHO GTPases may contribute to explain their singular biologic behavior

Ovarian clear cell carcinoma is found more often confined to the ovary (stage I) than high-grade serous carcinoma. The RHO GTPase family of proteins is involved in tumor invasion and metastasis through regulation of the cytoskeleton. The expression of several RHO family genes, including RHOA, RHOC, CDC42, and 3 ARHGDIs (Rho GDP dissociation inhibitors), was studied by real-time polymerase chain reaction in 22 clear cell carcinomas and 31 high-grade serous carcinomas. Immunoreaction for p21-activated kinase 1 (a downstream effector of CDC42) was also investigated on 6 tissue microarrays containing 76 carcinomas (13 clear cell carcinomas and 63 high-grade serous carcinomas). Eight clear cell carcinomas (8/21; 38%) were at stage I, whereas only 3 high-grade serous carcinomas (3/31; 10%) were at stage I. Postoperatively, all patients were treated with taxane and cisplatinum or carboplatinum. ARHGDIA messenger RNA expression was higher in clear cell carcinomas than high-grade serous carcinomas (P = .07). In contrast, CDC42 messenger RNA levels were lower in clear cell carcinomas than high-grade serous carcinomas (P = .02). Immunoreaction for p21-activated kinase 1 was concordant with the results obtained by real-time polymerase chain reaction for CDC42. In clear cell carcinomas, RHOA and RHOC messenger RNA expression was lower in stage I than in advanced-stage tumors (P = .03 and P = .005, respectively). Furthermore, in high-grade serous carcinomas, RHOA expression was higher in patients who did not respond to chemotherapy (P = .04). ARHGDIA, CDC42, RHOA, and RHOC expression may contribute to explain the different stage at diagnosis of clear cell and high-grade serous carcinomas. RHOA may cause resistance of high-grade serous carcinoma to chemotherapy.     

p63基因在肺癌组织中的表达

目的研究肺鳞状细胞癌、腺癌、大细胞肺癌、小细胞肺癌以及淋巴结或肺内转移性肿瘤标本组织中p63基因的mRNA转录因子和蛋白表达水平,探讨p63基因表达与其定位在3q 27-q29区域改变的关系.方法采用cDNA微阵列技术同时检测72例不同病理组织学类型的原发性肺癌(包括鳞状细胞癌、腺癌、大细胞癌、小细胞癌)和肺癌肺内转移及淋巴结转移灶内的p63基因mRNA水平.另外,利用组织芯片技术构建150例原发性肺癌石蜡包埋标本组织芯片,采用免疫组织化学LSAB法检测p63基因蛋白表达情况.同时应用比较基因组杂交(CGH)技术对70例原发性肺癌标本进行了3号染色体长臂改变的分析.结果p63mRNA转录因子在肺鳞状细胞癌标本表达明显增强,与腺癌、大细胞癌、小细胞癌相比增多10倍以上.肺癌转移灶内p63基因mRNA表达水平明显高于其相对应的原发性灶,差异有统计学意义(P＜0.001).免疫组织化学染色结果显示肺鳞状细胞癌阳性表达率为94.64%;腺癌是1.79%;4例大细胞肺癌中2例为阳性染色;但所有小细胞肺癌标本免疫组织化学染色均为阴性.pT1分期肺癌的p63基因蛋白表达阳性率与pT2分期肺癌相比有统计学差异(P＜0.05).比较基因组杂交结果发现肺鳞状细胞癌3号染色体长臂27-29区域有显著的扩增,腺癌表现为缺失.鳞状细胞癌p63基因的表达增强与3q27-q29区域的显著扩增有明显正相关性(P＜0.000 1),说明定位于3号染色体长臂27-29区域的p63基因的拷贝有明显的扩增.结论p63mRNA转录因子和蛋白在肺鳞状细胞癌较其他肿瘤表达显著增高,转移灶高于原发灶;肺鳞癌p63表达增强与3号染色体长臂3q27-q29区域的扩增显著相关.     

Immunohistochemical localization of the NM23 protein in salivary gland neoplasms with distinct biological behavior

The NM23 protein was shown to be associated with metastasis suppression in human malignancies with various tissue origins. However, its association with the metastatic phenotype of salivary gland neoplasms (SGN) remains unknown. To evaluate the role of NM23 in SGN, the expression patterns of NM23 in the following were compared: benign (pleomorphic adenoma) vs malignant (adenoid cystic carcinoma and mucoepidermoid carcinoma) SGN, and primary malignancies with/without evidence of metastasis vs their metastatic implants (MI). The lesions were studied immunohistochemically. NM23 protein was found in the cytoplasm of 75% of benign SGN, 73.3% of primary SGN malignancies with no evidence of metastasis, 86.6% of primary SGN malignancies with evidence of metastasis, and 60% of MI. There was no statistically significant difference in the frequency of NM23-positive cells between benign and primary malignant tumors (p = 0.79), nor between primary malignancies with/without evidence of metastasis and MI (p = 0.51). However, nuclear NM23 protein was restricted to primary SGN malignancies with evidence of metastasis and MI. The presence of nuclear NM23 protein may be a good marker for predicting the metastatic potential of SGN malignancies.     

c—erbB—2和p53基因表达与胃癌浸润转移的关系

目的：探讨胃癌组织中c-erbB-2和p53基因的表达与胃癌发生和浸润转移的关系。方法：应用荧光原位杂交技术对55例胃癌的常规石蜡标本进行检测,结果：c-erbB-2和p53基因表达的阳性率分别为36．6％和45．45％,其中在肠型和弥漫型胃癌中,c-erbB-2和p53阳性率分别为51．615和16．67％,p53阳性率分别为25．81％和70．83％,两种基因在两型间的差异有显著性意义（P＜0．05）,c-erbB-2和p53基因表达与胃的组织分级有关（分别为P＜0．05及P＜0．01）c-erbB-2和p53基因表达与胃癌的浸润深度有相关性（分别为P＜0．01及＜0．05）,c-erbB-2;基因表达与胃癌的淋巴结内转移有显著性意义（P＜0．05）,结论：c-rebB-2和p53基因有助于确定胃癌的生物学行为。     

The chemokine receptor CCR7 is expressed on epithelium of non-inflamed gastric mucosa, Helicobacter pylori gastritis, gastric carcinoma and its precursor lesions and up-regulated by H. pylori

CCR7 chemokine-receptor expression on tumour cells of gastric carcinoma has been associated with lymph-node metastasis and is thought to play an important role in metastasis. However, so far it is unknown whether CCR7 is newly up-regulated on gastric carcinoma or already expressed in non-neoplastic gastric epithelium. Therefore, epithelial CCR7 expression was investigated in the process of gastric carcinogenesis: non-inflamed mucosa --Helicobacter pylori gastritis -- intestinal metaplasia/dysplasia -- gastric carcinoma. CCR7 was expressed by gastric epithelium in non-inflamed gastric mucosa (n = 5), H. pylori gastritis (n = 17), intestinal metaplasia (n = 10), dysplasia (n = 3) and on tumour cells in 20 of 24 patients with gastric carcinoma (13/14 intestinal-type; 7/10 diffuse-type) as tested by immunohistochemistry. As CCR7 expression by gastric epithelium was significantly stronger in H. pylori gastritis than in non-infected mucosa, the influence of H. pylori on CCR7 receptor expression of gastric epithelial cells was investigated by fluorescence activated cell sorter analysis. H. pylori strains up-regulated the CCR7 chemokine-receptor in CCR7-positive cell lines. No difference in CCR7 up-regulation between cag(+) and cag(-)H. pylori strains was found. Epithelial CCR7 up-regulation by H. pylori may alter the metastatic fate of gastric carcinoma. Additionally, CCR7 expression not only on gastric carcinoma, but also on non-neoplastic gastric epithelium, suggests a novel biological function.     

Loss of phenotypic expression is related to tumour progression in early gastric differentiated adenocarcinoma

AIMS : To evaluate the relationship between phenotypic expression and tumour progression as represented by macroscopic features, submucosal invasion and lymph node metastasis in early differentiated gastric adenocarcinoma. METHODS : One hundred and fifty-five cases of early gastric differentiated adenocarcinoma without any poorly differentiated components were studied. The mucosal and submucosal components of carcinomas and lymph node metastatic lesions were classified into four categories, gastric type (G-type), incomplete intestinal type (I-type), complete intestinal type (C-type) and unclassified type (U-type), based on the combination of the phenotypic expression of HGM (gastric foveolar epithelium), MUC 6 (gastric pyloric glands), MUC 2 (intestinal goblet cells) and CD 10 (small intestinal brush border). In addition, a new classification representing a phenotypic shift from mucosa to submucosa or from primary lesion to lymph node metastasis was established with the categories of preserved group (P-group), loss group (L-group) and acquired group (A-group). RESULTS : (1) In submucosal carcinoma, U-type was more common in the submucosa (39%) than in the mucosa (9%). (2) U-type was more common in the metastatic lesions (42%) than in the primary lesions (5%). (3) The submucosal component and lymph node metastatic lesions were classified as P-group in 48% and 43% of cases, respectively, and as L-group in 50% and 52% of cases, respectively. (4) Lymph node metastatic lesions comprising undifferentiated carcinoma were classified as L-group in 100% of cases. CONCLUSION : During the course of tumour progression, early differentiated adenocarcinoma at first tends to lose its phenotypic expression despite preserving its morphology, but subsequently morphological dedifferentiation occurs.     

Primary tumour expression of the cysteine cathepsin inhibitor Stefin A inhibits distant metastasis in breast cancer

Using the clinically relevant 4T1-derived syngeneic murine model of spontaneous mammary metastasis to bone, we have identified the cysteine cathepsin inhibitor Stefin A as a gene differentially expressed in primary and metastatic mammary tumours. In primary tumours, Stefin A expression correlated inversely with metastatic potential in 4T1-derived lines and was not detected in tumour cells in culture, indicating induction only within the tumour microenvironment. Enforced expression of Stefin A in the highly metastatic 4T1.2 cell line significantly reduced spontaneous bone metastasis following orthotopic injection into the mammary gland. Consistent with the mouse data, Stefin A expression correlated with disease-free survival (absence of distant metastasis) in a cohort of 142 primary tumours from breast cancer patients. This was most significant for patients with invasive ductal carcinoma expressing Stefin A, who were less likely to develop distant metastases (log rank test, p = 0.0075). In a multivariate disease-free survival analysis (Cox proportional hazards model), Stefin A expression remained a significant independent prognostic factor in patients with invasive ductal carcinoma (p = 0.0014), along with grade and progesterone receptor (PR) status. In human lung and bone metastases, we detected irregular Stefin A staining patterns, with expression often localizing to micrometastases (<0.2 mm) in direct contact with the stroma. We propose that Stefin A, as a cysteine cathepsin inhibitor, may be a marker of increased cathepsin activity in metastases. Using immunohistology, the cathepsin inhibitor was detected co-expressed with cathepsin B in lung and bone metastases in both the murine model and human tissues. We conclude that Stefin A expression reduces distant metastasis in breast cancer and propose that this may be due to the inhibition of cysteine cathepsins, such as cathepsin B.