Effect of 5-fluorouracil on the expression of ATP-binding cassette superfamily G member 2 in human colon cancer cell SW480 / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the effect of 5-fluorouracil (5-FU) on the expression of ATP-binding cassette superfamily G member 2 (ABCG2) in human colon cancer cell SW480.</p><p><b>METHODS</b>SW480 cells were treated with various concentrations of 5-FU. CCK8 assay was utilized to detect the 5-FU IC50 to SW480 cells. Positive expression of ABCG2 was detected by flow cytometry, and mRNA expression of ABCG2 was detected by real time polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>The 5-FU IC50 to SW480 cells increased as the drug concentration increased (P<0.05). Flow cytometry revealed that positive expression rate of ABCG2 in normal SW480 cells (group A) was (6.26±0.86)%. Immediately after treatment with 5-FU for 48 hours, the positive expression rate of ABCG2 (group B) was (3.43±1.18)% (P<0.05). In the second passage of cells after treatment with 5-FU for 48 hours, the positive expression rate of ABCG2 (group C) was (12.91±3.42)% (P<0.05). The mRNA expression of ABCG2 detected by RT-PCR was in accordance with the results from flow cytometry.</p><p><b>CONCLUSION</b>Expression of ABCG2 in SW480 cells can be affected by various concentrations of 5-FU.</p>

Clinical significance of CC3/TIP30 expression in breast carcinoma and its correlation with HER-2/neu / 中华外科杂志

<p><b>OBJECTIVE</b>To explore the clinical significance of CC3/TIP30 protein's expression in breast carcinoma and its correlation with HER-2/neu.</p><p><b>METHODS</b>The expression of CC3/TIP30 and HER-2/neu protein was detected in 112 breast cancer tissues which was collected from January 2004 to January 2005 by immunohistochemistry and the relationship with clinic pathological parameters and prognosis was analyzed. Small interfering RNA (siRNA) which target to knock out CC3/TIP30 were transfected into SK-BR-3 cells. Real-time PCR were used to detect the level of CC3/TIP30 and HER-2/neu mRNA.</p><p><b>RESULTS</b>The results of immunohistochemistry showed CC3/TIP30 protein was correlated with TNM stage, lymph node status, HER-2 status and molecule classification (P = 0.048, 0.019, 0.027, 0.011), but there was no association with age, tumor size, estrogen receptor and progesterone receptor. Real-time PCR results revealed that CC3/TIP30 siRNA down-regulation the level of its mRNA, accompanied by a decline in the expression of HER-2/neu gene mRNA, the difference was statistically significant (F = 56.797, P = 0.000; F = 165.101, P = 0.000). In addition, Kaplan-Meier curves of disease-specific survival analysis showed a marked difference in the subtype of HER-2 protein positive between CC3/TIP30 positive group and negative group (χ(2) = 10.732, P = 0.001).</p><p><b>CONCLUSIONS</b>The loss of CC3/TIP30 is related to occurrence and development in breast cancer, suggesting early onset of metastasis and recurrence. Perhaps CC3/TIP30 can be considered as a sub-typing indicator in HER-2 positive breast cancer.</p>

Expression and its clinical significance of miR-155 in human primary breast cancer / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the expression of the miR-155 in human primary breast cancer and its clinical significance.</p><p><b>METHODS</b>From February to June 2009, 45 pairs of specimens of human primary breast cancer and matched nontumor breast tissues were collected from the patients who received operation for breast cancer. Real-time polymerase chain reaction (RT-PCR) was used to detect the miR-155 expression in those specimens.</p><p><b>RESULTS</b>The stem-loop RT-PCR was sensitive and specific enough to detect the expression of the miR-155. The median relative expression of miR-155 was 0.360 in tumor samples, and it was 0.135 in matched nontumor breast tissues, the difference was statistically significant (P < 0.05). It's indicated that the up-regulation of miR-155 expression was associated with advanced TNM clinical stage (median 0.316, 0.358 and 0.417 respectively for stage I, II and III tumor, P = 0.002), lymph node metastasis (median 0.383 and 0.355 respectively for cases with positive and negative lymph nodes, P = 0.034), higher proliferation index [median 0.387 and 0.353 respectively for cases with high proliferation index (Ki67 > 10%) and low proliferation index (Ki67 ≤ 10%), P = 0.019], estrogen receptor-positive (0.367 and 0.318 respectively for cases with positive estrogen receptor and negative group, P = 0.041) and progesterone receptor-positive (0.398 and 0.335 respectively for cases with positive progesterone receptor and negative group, P = 0.029) in patients with breast cancer.</p><p><b>CONCLUSIONS</b>The expression of miR-155 is up-regulated in primary breast cancer, especially in patients with positive estrogen and progesterone receptor. miR-155 may play an important role in the proliferation, invasion and metastasis of human primary breast cancer, and it could be a indicator in the diagnosis and prognosis of primary breast cancer.</p>

The effect of cyclooxygenase-2 on lymphangiogenesis in breast cancer / 中华外科杂志

<p><b>OBJECTIVE</b>To study the effect of cyclooxygenase-2 (COX-2) on lymphangiogenesis in breast cancer.</p><p><b>METHODS</b>By the means of immunohistochemistry, COX-2, vascular endothelial growth factor-C (VEGF-C) and D2-40 were examined in the tissue samples of primary tumors from 94 patients underwent surgical resections for breast cancer from November 1998 to March 2002. Eighty-three patients were followed-up. The expressions of VEGF-C mRNA and protein were detected by reverse transcription polymerase chain reaction (RT-PCR) and Western blot in MDA-MB-231 cell lines by the treatment of selective COX-2 inhibitor Nimesulide at different doses. The expressions of VEGF-C protein were evaluated in MDA-MB-231 cells treated by PGE2 (1 microg/ml) and Trastuzumab (1 microg/ml), respectively.</p><p><b>RESULTS</b>COX-2 over-expression was observed in 46.8% of surgical specimens (44/94), while VEGF-C overexpression occurred in 51.1% of tumor samples (48/94). COX-2 was strongly correlated with VEGF-C expression (P < 0.01), micro-lymphatic vessels (P = 0.032) and metastatic lymph nodes (P = 0. 035). Patients with COX-2 positive tumors had a significant shorter survival time than those with negative tumors did, including disease-free survival (P = 0.010) and overall survival (P = 0.040). Nimesulide could down-regulate the expressions of VEGF-C mRNA and protein in a does-dependent manner, while PGE2 could up-regulate the expressions. The expression of VEGF-C protein up-regulated by PGE2 treatment was decreased by Trastuzumab.</p><p><b>CONCLUSIONS</b>COX-2 over-expression can up-regulate the expression of VEGF-C. VEGF-C might promote lymph node metastasis by a lymph-angiogenic pathway, then affect the prognosis of the patients with breast cancer.</p>

The effect of selective cyclooxygenase-2 inhibitor nimesulide on breast cancer induced by dimethylbenzoic acid in rats / 中华外科杂志

<p><b>OBJECTIVE</b>To study the effect of nimesulide (NIM) on the tumorigenesis of mammary tumors induced by dimethylbenzoic acid (DMBA), and to investigate possible mechanisms of NIM against tumors.</p><p><b>METHODS</b>The studied rats were randomly divided into four groups: experimental control group, NIM group, diet and drug of NIM control group. The incidence of mammary tumor was observed. RT-PCR, Western blot were used to detect 8 cancerous tissues in every group, randomly. The expressions of cylooxygenase-2 (COX-2) were assessed by immunohistochemistry. The levels of prostaglandin E(2) (PGE(2)) in blood plasma and tumor tissues were determined by means of radio-immunity assay. The apoptosis index and the proliferation index were evaluated by TUNEL assay, immunohistochemical staining for proliferating cell nuclear antigen (PCNA), respectively.</p><p><b>RESULTS</b>The incidence of mammary tumor was 69.2% in experimental control group, 40.3% in NIM group. There was obviously decreased incidence in NIM group; The expressions of COX-2 mRNA and protein were significantly down-regulated in NIM group compared with experimental control group. The increased levels of PGE(2) synthesis in blood plasma and tumor tissues were significantly decreased by administering NIM (P < 0.05). The apoptosis index was obviously higher, the proliferation index was markedly less in NIM group than experimental control group.</p><p><b>CONCLUSIONS</b>Nimesulide could inhibit the tumorigenesis and development of DMBA-induced mammary tumors by inhibition of proliferation and induction of apoptosis. COX-2 and COX-2-mediated PGE(2) synthesis may play an important role in rat DMBA-induced breast cancer.</p>