- Email: [email protected]
Phenylacetate enhances the effect of chemotherapy on colon cancer cells
>lOOmM. To investigate mechanism(s) for decreasedcell number, we evaluatedcell proliferation by assessing PCNA expression. PEG did not alter PCNA levels. However, PEG treatment resulted in a dose-dependent induction in apoptosis, with 50 mM PEG increasing the apoptosis rate to 84-+3 % (r2= 0.78). This data was duplicated using another human colon cancer cell line, CaCo-2. Finally, to investigate potential mechanism(s) of apoptosis, we assessed par-4 expression, a pro-apoptotic protein recently implicated in NSAID-induced apoptosis (Zhang and DuBois Gastroenterology 2000;118:1012-17). Treatment with 50 mM PEG dramatically induced par-4 expression to 17-fold over vehicle (p
3126 Phenylacetate Enhances The Effect Of ChemotherapyOn Colon Cancer Cells Petr Protiva, St Luke's-Roosevelt Hosp Ctr, New York, NY; Banke Agarwal, M D Anderson Cancer Ctr, Houston, IX; Peter R. Holt, St Luke's-Roosevelt Hosp Ctr, New York, NY Background: Phenylacetate(PA) induces apoptosis and inhibits in-vitro intestinal cell growth by G1/S arrest. If PA can enhance chemotherapeutic or chemopreventive effects on colon cancer cells is unknown. Aims: We tested the hypothesis that PA enhances the effect of 2 chemotherapeutic agents, 5' fluorouracil (FU) and cispiatin (cPt) and 2 chemopreventivedrugs celecoxib (CE) and sulindac sulfone (SS) on colon cancer cell viability. Methods: SW-480 and HCT-116 colon cancer cell lines were incubated for 36 h with FU (10 and 20 mg/ml), cPt (5 and 10 mg/ml), CE 50 mM and SS 500 mM, respectively, _+ PA 25 mM Untreated cells served as controls (C). Cell viability was assessed by Ml-r assay. Results are expressed as percent of viability of controls _+SO (Figure). Conclusions: PA enhances the effect of chemotherapeutic/chemopreventiveagents on colon cancer cells. PA is safe and quite nontoxic in humans. Therefore, we suggest, that 1) addition of PA to chemotherapy may improve outcome in colorectal cancer; 2) PA may improve chemoprevention of colorectal cancer.
*
2~
.
.
HCT-l-116: lower part
.
.
.
*
[
.
SW-480: upper part
*P
**P
Celt Lines
Se9-1
Bic-I
Kyse-70
Yes-3
Carcinoma Androgen Rec. Apogenin Chry~n Luteolin
Adeno + 036±021. 050_+0.29* 0.55±0.09*
Adeno + 0.49-+022 * 0.54+_013. 059-+0.11 *
Squamous
Squamous
0.93_+0.09 "~ 0.95 +- 0.09 T 1.11_+0.101"
not tested 0.80+0.03 0.87_+0.06
means¢ standarddevi~on • versusT = significamdifferenceby ANOVA (p _<0.05)
11w hddldtoq Effect of Loeaofatin on the Growth of Human Gastric Carcinoma Cells In vitro JayoungKoo, Wonsup Oh, Kosin Univ, Gospel Hosp, Pusan South Korea; Kunyoung Park, Pusan National Univ, Pusan South Korea; Mooin Park, Seunja Park, Kosin Univ, Gospel Hosp, Pusan South Korea BackgroundslAJms : In the presentstudy the effects of Iovastatin, an inhibitor of HMG-CoA reductase, on the growth of human gastric carcinoma cell line, AGS cells were examined with or without the addition of 5-fluorouracil(5-FU). Cell cycle analysis was done to examine the mechanisms for the inhibitory effects of Iovastatin. Materials/Methods : The growth of AGS cells were examined by counting cell number on one and three days treatment with 0.2 ~mol/ L, 0.4 ~mol/L, 0.8 ~mol/L, 1.6~mol/L, 3.2 ~imol/L Iovastatin, and 0.1 ~g/ml, 0.3 ~g/ml 5-FU, after plating AGS cells into 35-mm2 plastic dishes at a density of 10/, cells/dish. The reversibility of the effects of Iovastatin was examined on one day to seven days treatment with 0.8 ~Imol/L Iovastatin after seeding 10i104 cells/dish. To examine the mechanisms for the inhibitory effects of Iovastatin, cell cycle analysis was done on the cells after tour days treatment with 0.8 ~imol/L Iovas~tin. Results : Lovastatin significantly inhibited the growth of AGS cells in a dose-dependent fashion(p
3127
COX-2 Specific Inhibitor Reduces Pancreatic Cancer Ceil Invasion Through Alteration of Cellular Adhesion and MMP Activation. Jiro Okami, Shoji Nakamori, Maseto Sakon, Hirofumi Yamamoto, Nobuaki Hiraok, Masanori Tsujic, Nobuyasu Hayashi, Ken Shiozaki, Hiroaki Nagano, Keizo Dono, Koji Umeshita, Morito Monden, Graduate Sch of Medicine, Osaka Univ, Suita Japan
Phytoestregens Inhibit Cell Proliferation and Induce Apoptosis in Esophageal Adeuocarcinoma Cell Lines Expressing the Androgen Reeeptor. Petra H. Nass, Johns Hopkins Univ Bayview Medical Ctr, Baltimore, MD; Colman K. Byrnes, The Johns Hopkins Univ Medical Ctr, Baltimore, MD; Joon Shim, Mark D. Duncan, Brian E, Lacy, Michael D. Crowell, John W. Harmon, Johns Hopkins Univ Bayview Medical Ctr, Baltimore, MD
[Background and Aim] Cyclooxygenase(COX) is a rate-limiting enzyme involved in the conversion of arachidonic acid to prostaglandin H. One isoform of the enzyme, COX-2, is an inducible enzyme synthesized at inflammatory lesions and malignant tumors. We have previously reported that COX-2 is overexpressed in pancreatic cancer tissues although only faint expression is observed in benign pancreatic tumors. To clarify how COX-2 involves malignant behavior of pancreatic cancer, we studied the effect of COX-2 specific inhibitor on cell invasion in COX-2 expressing pancreatic cancer cells. [Methods] COX-2 expressing pancreatic cancer cell lines, PSN-1 and KMP-4, were used for this study. Their invasiveness was tested with the Boyden chamber invasion assay using Matrigel coated 8 p.m polycarbonate filters. To assessthe effect of COX-2 inhibitor, 0 and 50/~M of JTE-522 (COX-2 specific inhibitor, gifted by JT Corporation) was added in both the upper and the lower chambers. Fibronectin (10 /~g/ml) was used as chemoaftractant. For adhesion experiments, the pretreated cells with 0 and 5 0 / ~ of JTE-522 for 48 hours were seeded on 96-well plates coated with BSA (for control), fibronectin, and collagen type I. After incubation for 1 hour, adherent cells were spectrophotometricaly quantified by staining with methyleneblue. Gelatin zymography was carried out to evaluate the effects of COX-2 inhibitor on induction of MMP-9 and activation of MMP-2 by Concanavalin A (Con-A). Supernatants of culture medium were collected after 24-48 h incubation with 0 and 50 t~M of JTE-522 and analyzed. [Result] In a Matrigel invasion assay, the number of invading cells was significantly (p
INTRODUCTION - A group of phytochemicals, referred to as phytoestrogens, have structural similarity to sex hormones and have been shown to modulate androgen and progesterone receptors in hormone-dependent prostate and breast cancer cell lines. Some esophageal cancers express the androgen receptor and may therefore be sensitive to phytoestrogens as has been describedfor prostate and breast cancer. The objective of this study was to investigate the therapeutic potential of phytoestrogens in esophageal cancer cell lines with regard to androgen receptor expression. MATERIALS AND METHODS - Four esophageal cancer cell lines were used in this study (see Table). The three phytoestrogens, apogenin, chrysin, and luteolin were tested in a MIT based cell proliferation assay at concentrations from 1 to 50 p,M in 96-well cell culture plates. Apoptosis was demonstrated by DNA fragmentation. Androgen receptor expression was determined by RT-PCRand Western blot. RESULTS- Apogenin, Chrysin, and Luteolin preferentially inhibited cell proliferation of the androgen receptor positive adenocarcinomacell lines Seg-1 and Bic-1 in a dose-dependentmanner. The androgen receptor negative (AR-) cell line Kyse-70 was not affected. The (AR-) cell line Yes-3 was weakly inhibited. Proliferation indexes (A57o.6~treated versus control cells) for a concentration of 50 p,M are listed in the table. The inhibition of cell proliferation was accompanied by an increase in apoptosis as demonstrated by DNA fragmentation. CONCLUSION* These results indicate that phytoestrogens may preferentially inhibit the growth of adenocarcinoma cancer cells expressing the androgen receptor and demonstrate a therapeutic potential of phytoestrogens for esophageal cancer.
A-616
3126 Phenylacetate Enhances The Effect Of ChemotherapyOn Colon Cancer Cells Petr Protiva, St Luke's-Roosevelt Hosp Ctr, New York, NY; Banke Agarwal, M D Anderson Cancer Ctr, Houston, IX; Peter R. Holt, St Luke's-Roosevelt Hosp Ctr, New York, NY Background: Phenylacetate(PA) induces apoptosis and inhibits in-vitro intestinal cell growth by G1/S arrest. If PA can enhance chemotherapeutic or chemopreventive effects on colon cancer cells is unknown. Aims: We tested the hypothesis that PA enhances the effect of 2 chemotherapeutic agents, 5' fluorouracil (FU) and cispiatin (cPt) and 2 chemopreventivedrugs celecoxib (CE) and sulindac sulfone (SS) on colon cancer cell viability. Methods: SW-480 and HCT-116 colon cancer cell lines were incubated for 36 h with FU (10 and 20 mg/ml), cPt (5 and 10 mg/ml), CE 50 mM and SS 500 mM, respectively, _+ PA 25 mM Untreated cells served as controls (C). Cell viability was assessed by Ml-r assay. Results are expressed as percent of viability of controls _+SO (Figure). Conclusions: PA enhances the effect of chemotherapeutic/chemopreventiveagents on colon cancer cells. PA is safe and quite nontoxic in humans. Therefore, we suggest, that 1) addition of PA to chemotherapy may improve outcome in colorectal cancer; 2) PA may improve chemoprevention of colorectal cancer.
*
2~
.
.
HCT-l-116: lower part
.
.
.
*
[
.
SW-480: upper part
*P
**P
Celt Lines
Se9-1
Bic-I
Kyse-70
Yes-3
Carcinoma Androgen Rec. Apogenin Chry~n Luteolin
Adeno + 036±021. 050_+0.29* 0.55±0.09*
Adeno + 0.49-+022 * 0.54+_013. 059-+0.11 *
Squamous
Squamous
0.93_+0.09 "~ 0.95 +- 0.09 T 1.11_+0.101"
not tested 0.80+0.03 0.87_+0.06
means¢ standarddevi~on • versusT = significamdifferenceby ANOVA (p _<0.05)
11w hddldtoq Effect of Loeaofatin on the Growth of Human Gastric Carcinoma Cells In vitro JayoungKoo, Wonsup Oh, Kosin Univ, Gospel Hosp, Pusan South Korea; Kunyoung Park, Pusan National Univ, Pusan South Korea; Mooin Park, Seunja Park, Kosin Univ, Gospel Hosp, Pusan South Korea BackgroundslAJms : In the presentstudy the effects of Iovastatin, an inhibitor of HMG-CoA reductase, on the growth of human gastric carcinoma cell line, AGS cells were examined with or without the addition of 5-fluorouracil(5-FU). Cell cycle analysis was done to examine the mechanisms for the inhibitory effects of Iovastatin. Materials/Methods : The growth of AGS cells were examined by counting cell number on one and three days treatment with 0.2 ~mol/ L, 0.4 ~mol/L, 0.8 ~mol/L, 1.6~mol/L, 3.2 ~imol/L Iovastatin, and 0.1 ~g/ml, 0.3 ~g/ml 5-FU, after plating AGS cells into 35-mm2 plastic dishes at a density of 10/, cells/dish. The reversibility of the effects of Iovastatin was examined on one day to seven days treatment with 0.8 ~Imol/L Iovastatin after seeding 10i104 cells/dish. To examine the mechanisms for the inhibitory effects of Iovastatin, cell cycle analysis was done on the cells after tour days treatment with 0.8 ~imol/L Iovas~tin. Results : Lovastatin significantly inhibited the growth of AGS cells in a dose-dependent fashion(p
3127
COX-2 Specific Inhibitor Reduces Pancreatic Cancer Ceil Invasion Through Alteration of Cellular Adhesion and MMP Activation. Jiro Okami, Shoji Nakamori, Maseto Sakon, Hirofumi Yamamoto, Nobuaki Hiraok, Masanori Tsujic, Nobuyasu Hayashi, Ken Shiozaki, Hiroaki Nagano, Keizo Dono, Koji Umeshita, Morito Monden, Graduate Sch of Medicine, Osaka Univ, Suita Japan
Phytoestregens Inhibit Cell Proliferation and Induce Apoptosis in Esophageal Adeuocarcinoma Cell Lines Expressing the Androgen Reeeptor. Petra H. Nass, Johns Hopkins Univ Bayview Medical Ctr, Baltimore, MD; Colman K. Byrnes, The Johns Hopkins Univ Medical Ctr, Baltimore, MD; Joon Shim, Mark D. Duncan, Brian E, Lacy, Michael D. Crowell, John W. Harmon, Johns Hopkins Univ Bayview Medical Ctr, Baltimore, MD
[Background and Aim] Cyclooxygenase(COX) is a rate-limiting enzyme involved in the conversion of arachidonic acid to prostaglandin H. One isoform of the enzyme, COX-2, is an inducible enzyme synthesized at inflammatory lesions and malignant tumors. We have previously reported that COX-2 is overexpressed in pancreatic cancer tissues although only faint expression is observed in benign pancreatic tumors. To clarify how COX-2 involves malignant behavior of pancreatic cancer, we studied the effect of COX-2 specific inhibitor on cell invasion in COX-2 expressing pancreatic cancer cells. [Methods] COX-2 expressing pancreatic cancer cell lines, PSN-1 and KMP-4, were used for this study. Their invasiveness was tested with the Boyden chamber invasion assay using Matrigel coated 8 p.m polycarbonate filters. To assessthe effect of COX-2 inhibitor, 0 and 50/~M of JTE-522 (COX-2 specific inhibitor, gifted by JT Corporation) was added in both the upper and the lower chambers. Fibronectin (10 /~g/ml) was used as chemoaftractant. For adhesion experiments, the pretreated cells with 0 and 5 0 / ~ of JTE-522 for 48 hours were seeded on 96-well plates coated with BSA (for control), fibronectin, and collagen type I. After incubation for 1 hour, adherent cells were spectrophotometricaly quantified by staining with methyleneblue. Gelatin zymography was carried out to evaluate the effects of COX-2 inhibitor on induction of MMP-9 and activation of MMP-2 by Concanavalin A (Con-A). Supernatants of culture medium were collected after 24-48 h incubation with 0 and 50 t~M of JTE-522 and analyzed. [Result] In a Matrigel invasion assay, the number of invading cells was significantly (p
INTRODUCTION - A group of phytochemicals, referred to as phytoestrogens, have structural similarity to sex hormones and have been shown to modulate androgen and progesterone receptors in hormone-dependent prostate and breast cancer cell lines. Some esophageal cancers express the androgen receptor and may therefore be sensitive to phytoestrogens as has been describedfor prostate and breast cancer. The objective of this study was to investigate the therapeutic potential of phytoestrogens in esophageal cancer cell lines with regard to androgen receptor expression. MATERIALS AND METHODS - Four esophageal cancer cell lines were used in this study (see Table). The three phytoestrogens, apogenin, chrysin, and luteolin were tested in a MIT based cell proliferation assay at concentrations from 1 to 50 p,M in 96-well cell culture plates. Apoptosis was demonstrated by DNA fragmentation. Androgen receptor expression was determined by RT-PCRand Western blot. RESULTS- Apogenin, Chrysin, and Luteolin preferentially inhibited cell proliferation of the androgen receptor positive adenocarcinomacell lines Seg-1 and Bic-1 in a dose-dependentmanner. The androgen receptor negative (AR-) cell line Kyse-70 was not affected. The (AR-) cell line Yes-3 was weakly inhibited. Proliferation indexes (A57o.6~treated versus control cells) for a concentration of 50 p,M are listed in the table. The inhibition of cell proliferation was accompanied by an increase in apoptosis as demonstrated by DNA fragmentation. CONCLUSION* These results indicate that phytoestrogens may preferentially inhibit the growth of adenocarcinoma cancer cells expressing the androgen receptor and demonstrate a therapeutic potential of phytoestrogens for esophageal cancer.
A-616