Metastatic Bladder Cancer: Role of Chemotherapy and New Agents

In vitro antimetastatic effect of Changweiqing through antiinvasion of hypoxic colorectal carcinoma LoVo cells

OBJECTIVE

To investigate the in vitro effects and the primary mechanisms of Changweiqing (, CWQ) on antimetastasis and antiinvasion of hypoxic colon carcinoma cells. In addition, to provide experimental evidence for the Chinese medicinal theory of "strengthening the body's resistance to eliminate pathogenic factors" in the treatment of colorectal cancer, including its invasion and metastasis.

METHODS

First, CWQ sera were prepared with serum-pharmacology methods. Then, the modified hypoxic chamber was designed and flushed with 5% CO(2) and 95% N(2) at 37 °C to induce a hypoxic environment. The effect of CWQ serum on the viability of LoVo cells was tested with MTT cytotoxicity assay. The wound model and chamber model were established to estimate the effects of CWQ serum on migration and invasion of LoVo cells. The model for cell adhesion was established to evaluate the effect of CWQ serum on LoVo cells' adhesion. The gelatin zymography model was performed to determine the effects of CWQ serum on the activities of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9). The effects of CWQ serum on the hypoxia-inducible factor 1 α (HIF-1α) nuclear translocation and the mRNA level of vascular endothelial growth factor (VEGF) in LoVo cells were determined by Western blot and reverse transcription-polymerase chain reaction (RT-PCR) analyses, respectively.

RESULTS

CWQ inhibited LoVo cells' migration based on wound healing assay. The inhibitive effect could reach about 68.00% under hypoxic culture and about 29.87% under normoxic culture when cells were treated with 10% CWQ serum for 24 h. The results from both cell invasion and adhesion assays showed that CWQ serum could dose-dependently repress the invasion of LoVo cells and inhibit cells from adhering to extra cellular matrix (ECM). Under the hypoxic culture condition, RT-PCR analysis showed that 10% CWQ serum had down-regulated the expression of VEGF by 45.87%, and the result of Western blot analysis provided further evidence. The HIF-1α amount in the nucleus of the LoVo cells was also diminished in a dose-dependent manner, as shown by the Western blot. Gel zymogram assay revealed that CWQ serum could suppress the activities of MMP-2 and MMP-9.

CONCLUSIONS

CWQ could effectively inhibit tumor metastasis in vitro The antimetastatic effects of CWQ were associated with the inhibition of cell motility, which was evidenced by inhibition of cell invasion and adhesion. The molecular mechanisms of the inhibition of tumor invasion by CWQ were due to the reduced expression of both HIF-1α and VEGF and the suppression of MMP-2 and MMP-9 expression.

Differential effects of sulfated triterpene glycosides, holothurin A1, and 24-dehydroechinoside A, on antimetastasic activity via regulation of the MMP-9 signal pathway

Two sulfated triterpene glycosides, holothurin A(1) (HA(1)) and 24-dehydroechinoside A (DHEA), isolated from the sea cucumber Pearsonothuria graeffei, are of the holostane type with 18(20)-lactone and identical carbohydrate chains. DHEA has a side chain 23 (24)-double bond, while HA(1) has a hydroxyl group at C-21. In this study, we compared the effects of DHEA and HA(1) on metastasis in vitro and in vivo. The results show that HA(1) and DHEA treatment significantly suppressed adhesion of human hepatocellular liver carcinoma cells (HepG2) to both matrigel and human endothelial cells (ECV-304) and inhibited HepG2 cell migration and invasion in a dose-dependant manner. HA(1) and DHEA reduced tube formation of ECV-304 cells on the matrigel in vitro and attenuated neovascularization in the chick embryo using the chorioallantoic membrane (CAM) assay in vivo. Immunocytochemistry analyses revealed that both HA(1) and DHEA significantly decreased the expression of the matrix metallo-proteinase-9 (MMP-9) and increased the expression level of tissue inhibitor of metalloproteinase-1 (TIMP-1), an important regulator of MMP-9 activation. Western blot analyses demonstrated that HA(1) and DHEA remarkably abolished the expression of vascular endothelial growth factor (VEGF). The expression of nuclear factor-kappa B (NF-κB) was significantly decreased by HA(1), while DHEA treatment had no effect on the down regulation of NF-κB expression. These data suggest that both DHEA and HA(1) exert significant antimetastatic activities by inhibiting MMP-9 and VEGF expression. DHEA-induced antimetastasis was more potent than HA(1). In addition, only HA(1) treatment downregulated the expression level of NF-κB, suggesting that the antimetastatic activity of triterpene glycosides derived from P. graeffei can be either NF-κB-dependent or -independent, depending on their structure.

Antimetastatic effect of a lipophilic ascorbic acid derivative with antioxidation through inhibition of tumor invasion

PURPOSE

Ascorbic acid (AA), the natural antioxidant, has been demonstrated to exert an antimetastatic action; however, AA is quite unstable in physiological condition. The aim of the present study is to investigate the stability, the antioxidation and the antimetastatic effects of three lipophilic AA derivatives in vitro as well as in vivo.

METHODS

The 95D cells were treated with ascorbic acid-2-O-phosphate-6-O-laureate (AA2P6L), ascorbic acid-2-O-phosphate-6-O-myristate (AA2P6M) and ascorbic acid-2-O-phosphate-6-O-stearate (AA2P6S). AA derivatives' stability in medium under cell culture condition, in the presence and in the absence of 95D cells, was assessed by high-performance liquid chromatography assay. Cell viability and intracellular oxidative stress were measured by MTT assay and CDCFH assay, respectively. Wound healing assay and cell adhesion assay were used to investigate the antimetastatic activities against 95D cells in vitro, and the C57BL/6 mice model was used to evaluate the antimetastatic action in vivo.

RESULTS

All the three AA derivatives exhibited excellent stability, significantly different from AA. Results of MTT assay showed that IC(50) values of the cytotoxicity of those AA derivatives, namely AA2P6L, AA2P6M and AA2P6S, were 38.46, 28 and 22.97 microg/ml, while the CDCFH assay indicated that EC(50) values of antioxidant effects on 95D cells were 31.12, 33.51 and 38.31 microg/ml, respectively. Through the ratio of IC(50) vs EC(50) for AA derivatives, AA2P6L was demonstrated to be the most effective AA derivative, which retained the antioxidant ability as well as low cytotoxicity. AA2P6L dose-dependently inhibited 95D cells' migration and adhesion, by 50% at the concentration of 20 and 57 microg/ml, respectively. In the animal experiment, intraperitoneal administration of 75 mg/kg AA2P6L decreased the number of metastatic nodules by 62% and elevated the survival rate of C57BL/6 mice about onefold compared to the control group.

CONCLUSION

AA2P6L, a lipophilic AA derivative with antioxidation, is shown to be a potent antimetastatic agent through the inhibition of tumor invasion. These results support future investigations on the feasibility of cancer chemotherapy with AA2P6L.

["Second line" polychemotherapy in metastatic urothelial cancer of the renal pelvis. Persisting partial remission by 18 treatment cycles of gemcitabine/paclitaxel after 24 treatment cycles gemcitabine/cisplatin "stable disease"]

Moderate activity of systemic chemotherapy for advanced urothelial cancer has been reported for more than 30 years. Only with the advent of potent combination therapy in the mid-1980s have clinically significant response rates and prolonged survival been documented. Due to the small number of cases and poor prognosis, knowledge is scant about the therapeutic effect of "second-line" polychemotherapy in metastatic upper tract urothelial cancer. We report an interesting case of a 59-year-old man suffering from urothelial cancer of the renal pelvis with pulmonary, lymphogenous, and bone metastases who had an unexpected response to "second-line" chemotherapy with only 2 treatment cycles of gemcitabine/paclitaxel (partial remission) after 24 treatment cycles of gemcitabine/cisplatin in "stable disease" with progression between the therapeutic intervals.