Induction of p53 and drug resistance following treatment with cisplatin or paclitaxel in ovarian cancer cell lines

Treatment failures result from resistance to chemotherapy in ovarian cancer. The effect of cisplatin and paclitaxel treatments on chemosensitivity was studied in ovarian cancer cells developed from a patient with stage IIIC disease. Cells (UL-3A, UL-3B) that recovered from cisplatin (Cis) and paclitaxel (Tax) treatments showed higher levels of p53, mdr-1 and chemoresistance than untreated controls. EC50 values of Cis and Tax for UL-3A clones were 7.2-34.6, average 20.9 microg/ml, while UL-3B clones ranged from 11.8-252.0 microg/ml, with a mean value of 73.2 microg/ml for Cis, and 260.0-4400.0 nM (mean 2555.0 nM) for Tax. Selection pressures during treatment may contribute to drug resistance.     

SYNERGISTIC EFFICACY OF ADENOVIRUS-MEDIATED BCL-XS GENE TRANSFER AND TOPOTECAN IN OVARIAN CANCER CELL

Ovarian cancer is one of the three most frequent malignancy tumors in the female reproductive organ. The mortality of ovarian cancer is highest in the three malignancies. Recently, its diagnosis and therapy are improved, but the survival rate of 5 years is still poor. So it is important to improve the curative effect by molecule genetic methods. The genes of bcl-2 family can regulate apoptosis and influence the sensitivity of tumor to chemotherapy- induced apoptosis[1-6] In the bcl-2 famil…     

Intraperitoneal adenovirus-mediated suicide gene therapy in combination with either topotecan or paclitaxel in nude mice with human ovarian cancer

A mouse model of human ovarian cancer was used to investigate the effect of adenovirus-mediated thymidine kinase gene therapy (gt) in combination with chemotherapy. One hundred sixty female CD-1 nu/nu mice were injected intraperitoneally with Ov-ca-2774 cells. Onset of intraperitoneal treatment with either topotecan (6 or 12 mg/kg) or paclitaxel (18 or 36 mg/kg) was on day 4 or 8 and was repeated once after 4 days. Animals scheduled for gt received intraperitoneal application of adv/rsv-tk 1 day prior to chemotherapy and were subsequently treated with ganciclovir (gcv; 10 mg/kg, every 12 hours for 6 days). Survival was chosen as study endpoint. Whereas tumor burden had hardly any effect on survival, the lower dose of either cytotoxic agent was seen to be more effective than the higher one. In the topotecan group, an interaction between topotecan and gt was present. Survival was best for animals treated with low dose of topotecan only, the addition of gt reduced survival time significantly. With the higher dose, gt did not affect survival time. With paclitaxel, only slight effects of gt on the survival times were seen. Due to treatment toxicity, this animal model may be problematic for the evaluation of gt and chemotherapy combinations. The effect of dose varied strongly with time. Mice treated with high-dose chemotherapy had a substantially increased risk of dying in the time period following application, whereas this advantage of the lower dose disappeared later.     

Antitumor effect of adenovirus-mediated p53 family gene transfer on osteosarcoma cell lines

Osteosarcoma (OS) is one of the most common malignancies of the bone. Although prognosis of OS has improved significantly during the past several years due to more intensive chemotherapy and radiotherapy regimens, new therapeutic approaches are needed for recurrent and inoperable cases, p73 and p63, like their homologue, the tumor suppressor p53, are able to induce apoptosis in several cell types. Here, we evaluated the antitumor effects of p73 and p63 on eleven different human OS cell lines. In vitro, adenovirus-mediated transduction of p63gamma induced apoptosis in OS cells that are resistant to p53-mediated apoptosis, while less effect was observed following transduction of p73alpha or p63alpha. Interestingly, the apoptotic effects of p63gamma were greater than those of wild-type p53 in OS cells carrying MDM2-amplification. We then determined the in vivo therapeutic effect of intratumoral injection of adenovirus-vector expressing p53 family members on xenografts derived from Saos-2 cells implanted in nude mice, and showed that infection with p63y significantly suppressed tumor growth compared with p53. In addition, exogenous p73beta and p63gamma significantly increased the chemosensitivity of OS cells to doxorubicin and cisplatin, chemotherapeutic agents commonly used in the treatment of OS. Our results suggest that adenovirus-mediated transduction of p53 family members may have utility in gene therapy for OS, particularly in combination with chemotherapeutic agents.     

Efficient adenovirus-mediated gene transfer into human cancer cell lines derived from digestive tract

The efficiency of gene transfer into human cancer cells from digestive tract was evaluated using a replication-deficient recombinant adenovirus (Ad) vector harboring a lacZ gene of E. coli as a reporter gene (AxCALacZ). Average percent X-gal staining of esophageal cancer cell lines was 46%, that of gastric cancer cell lines 82% and that of colon cancer cell lines 70% at 3 days after Ad vector infection. X-gal staining in vitro continued 2 months after infection. By the direct injection of adenovirus vector to the tumors in nude mice, a certain percentage of tumor cells was stained by the X-gal. Colon26 cell line infected with AxCALacZ was implanted in BALB/c mice immunized with AxCALacZ, and tumor growth was suppressed. We presume this was due to anti-adenoviral immunity.     

Factors limiting adenovirus-mediated gene transfer into human lung and pancreatic cancer cell lines.

Adenoviral vectors are a widely used means of gene transfer. However, transgene expression after adenoviral administration varies among different carcinoma cell lines. We hypothesized that this variation is attributable, in part, to the presence of cell surface molecules involved in adenoviral infection. To test this, we first assessed adenovirus-mediated transgene expression in four human lung carcinoma cell lines and four human pancreatic carcinoma cell lines in terms of luciferase activities and found it to vary from 4.8 x 10(4) to 6.1 x 10(7) relative light units/microg of protein. Then, to determine whether the molecules involved in the entry of adenovirus into host cells were responsible for this variation, we evaluated the expression of alpha(v)beta5, alpha(v), beta3, alpha5, and beta1 integrins and that of coxsackievirus and adenovirus receptor (CAR) in these cell lines. Statistical analysis revealed that the levels of beta3 were associated with the levels of transgene expression. Blocking analysis showed that adenovirus-mediated gene transfer could be blocked by antibodies against these six molecules but not by the antibodies against alpha2 or alpha3 integrins, thus suggesting that the integrins alphavbeta5, alpha(v), beta3, alpha5, and beta1 and CAR molecules could limit adenovirus-mediated gene transfer when their levels fell below a certain threshold. Furthermore, cells expressing low levels of beta3 and resistant to conventional adenoviral vectors were susceptible to a vector containing the heparin-binding domain in its fiber, thus suggesting that redirecting vectors to receptors other than CAR may bypass the integrin pathway. These findings may have implications for improving the efficiency of adenovirus-mediated gene transfer and developing novel adenoviral vectors.     

RON and cisplatin resistance in ovarian cancer cell lines

RON (recepteur d'origine nantais) tyrosine kinase receptor has revealed its tumorigenic potential in recent studies. RON was reported to be overexpressed in 55% of primary ovarian carcinoma samples and furthermore its activation increases cell motility and invasiveness. In this study, we investigated the correlation between RON expression and chemoresistance in ovarian cancer cells. In A2780 cells, a model featured by high chemosensitivity to cisplatin, stable overexpression of RON was able to reduce sensitivity to this agent, while incubation with a blocking anti-RON antibody (ID1) increased the cisplatin-induced growth inhibition effect. Moreover, we observed an increased RON expression both at the mRNA and protein level in A2780 cells made resistant to doxorubicin and paclitaxel (A2780ADR and TC 1, respectively), two cell lines exhibiting a collateral resistance to cisplatin. OVCAR-3 cells, showing high levels of RON expression, also displayed inherent cisplatin resistance. The morphology observed in these resistant cells is consistent with a scattering phenotype and a RON-activated state. RON expression levels were monitored upon hypoxia. A 2.5-fold increase of RON expression was noticed in response to hypoxia in OVCAR-3 cells, in parallel with a decrease of E-cadherin mRNA. Altogether these results suggest an involvement of RON in the acquisition of cisplatin resistance and highlight the importance of this factor as a promising target for combination with cisplatin-based chemotherapy in ovarian cancer.     

DHMEQ enhances the cytotoxic effect of cisplatin and carboplatin in ovarian cancer cell lines

Ovarian cancer (OvCa) is one of the most lethal gynaecological malignancies. It is diagnosed mostly in advanced stages. Due to a lack of appropriate early detection markers and non-ambiguous symptoms, the five-year survival rate is significantly reduced. Despite a primary good response to platinum-based therapy, approximately 70% of patients will develop a chemoresistance phenotype. The activation of the NF-κB signalling pathway plays a crucial role in this process. It is responsible for increasing cell viability, cell cycle progression and induces growth and migration of neoplastic cells. A few independent studies have yet suggested a high correlation between activation of NF-κB and poor outcome in OvCa patients. Thus, developing inhibitors of the NF-κB pathway has become a new target of cancer therapies. One of the promising compounds is DHMEQ (dehydroxymethylepoxyquinomicin). Our preliminary studies indicated that DHMEQ combined with cisplatin (CDDP) or carboplatin (CBP) enhanced apoptosis in the A2780 cell line and caused cell cycle arrest in the G2/M phase in the SKOV3 cell line, but not in the normal cell line MRC-5 pd19. Moreover, the combination of those agents caused decreased motility of cells, especially with the CBP. However, the invasion of cells was not changed significantly. The analysis of drug interactions using CompuSyn software has revealed that observed effect of the doses used in the study was antagonistic, but the DRI guidelines and in vitro observation of biological response indicate that a combination of DHMEQ with CDDP or CBP could be a novel proposal in ovarian cancer treatment.     

Hepatocyte growth factor sensitizes human ovarian carcinoma cell lines to paclitaxel and cisplatin

The hepatocyte growth factor (HGF) receptor, encoded by the MET oncogene, is expressed in approximately 70% of human ovarian carcinomas and overexpressed in 30% of cases. Because HGF is known to protect cells from apoptosis, we investigated whether receptor expression modifies ovarian cancer cell response to chemotherapy. The apoptotic effect of the front-line chemotherapeutic drugs paclitaxel and cisplatin on cells treated with HGF was studied. In ovarian cancer cell lines, pretreatment with HGF surprisingly enhances the apoptotic response to low doses of paclitaxel and cisplatin. HGF empowers specifically the intrinsic apoptotic pathway, whereas it protects cells from extrinsic Fas-induced apoptosis. Chemotherapy sensitization is specific for HGF because another growth factor (e.g., epidermal growth factor) increases ovarian cancer cell survival. In nonovarian cancer cell models, as expected, HGF provides protection from drug-induced apoptosis. These data show that HGF sensitizes ovarian carcinoma cells to low-dose chemotherapeutic agents. This suggests that HGF may be used to improve response to chemotherapy in a set of human ovarian carcinomas molecularly classified based on the MET oncogene expression.     

紫杉醇联合顺铂治疗晚期非小细胞肺癌的临床观察

目的评价紫杉醇联合顺铂治疗非小细胞肺癌的临床疗效及毒性反应。方法紫杉醇150mg/m2静滴第1、8天,顺铂20mg静滴第1~5天,21天为1周期,治疗3个周期评价疗效。结果47例受治者,有效率为42.6%。毒副反应主要为恶心、呕吐、骨髓抑制。结论紫杉醇联合顺铂治疗非小细胞肺癌具有较好的疗效,毒副反应可以耐受。     

Weekly paclitaxel and cisplatin in recurrent ovarian cancer

This study was performed to assess the feasibility of weekly paclitaxel (TXL) and cisplatin (CDDP) in patients with recurrent ovarian cancer. Ten of eleven patients experienced recurrence after more than 6 months after first line CDDP-based chemotherapy. TXL and CDDP were given at initial doses of 60 mg/m2 and 30 mg/m2 on days 1, 8, and 15 in 2 patients and an increase in the respective dose level was planned to 60/35 in 5 patients, 70/35 in 2 patients, and 70/40 in 2 patients. Toxicities were well tolerated. None of the patients suffered from neurotoxicity or myalgia of more than grade 2. Gastrointestinal disorder was recognized as grade 1-2, and grade 3-4 hematological toxicity included leucocytopenia (64%), anemia (36%), and thrombocytopenia (9%). We set the recommended dose of TXL at 70 mg/m2 and that of CDDP at 35 mg/m2, considering toxicity and performed planned schedule. Of eleven patients, nine were assessable by computed tomographic scan. The overall response rate was 67% (CR: 1, PR: 5, NC: 1, PD: 2). One of two patients with standard TXL/CDDP therapy showed PR by switching to a weekly schedule. The median follow-up duration was 490 days and the median response duration was 371 days. From the results presented here, it is suggested that this regimen with increased DI might be quite effective and well tolerated in patients who experience relapse after CDDP-based chemotherapy.     

Studies on combinations of platinum with paclitaxel and colchicine in ovarian cancer cell lines

Ovarian cancer remains an ongoing challenge because of the occurrence of resistant forms of tumour for which the drugs fail to function. Combination therapy using drugs with different mechanisms of action offer a means of overcoming drug resistance and reducing the side-effects. In this study, binary combinations of four platinum compounds cisplatin (Cs), oxaliplatin (Ox), YH12 [trans-PtCl(2)(ammino) {imidazo-(1,2-α)pyridine}] and TH1 [{trans-PtCl(NH(3))(2)}(2) {trans-Pt(3-hydroxypyridine)(2)(H(2)N(CH(2)) 6NH(2))(2)}Cl(4)] and two plant-based mitotic inhibitors paclitaxel (Tx) and colchicine (Co) have been used against ovarian cancer cell lines A2780 and A2780(cisR) using five different sequences of addition: 0/0 h, 4/0 h, 0/4 h, 24/0 h and 0/24 h. The strongest synergistic effect was observed when the plant compound (Tx or Co) was added first followed by platinum four hours later with combination index at 50% effect level (fa= 0.5) ranging from 0.03 to 0.36 and 0.10 to 0.72 in A2780 and A2780(cisR) cells respectively. Of all the platinum compounds, Cs showed the greatest synergism when combined with Tx and Co (combination index, CI(50)=0.03 in A2780 and from 0.10 to 0.12 in A2780(cisR)). With the sequence 24/0 h, platinum compounds showed greater synergistic effect with Co than Tx in A2780(cisR). With the sequences 0/4 h and 0/24 h, most of the combinations showed weak synergism to antagonism, especially in A2780(cisR). Antagonism was also observed when the two compounds were added simultaneously, especially in A2780(cisR). CONCLUSION: Binary combinations of platinum compounds Cs, Ox, YH12 and TH1 with plant compounds Tx and Co applied to ovarian cancer cell lines showed sequence- and concentration-dependent synergism. The results may have profound implications in therapy, if found to be true in vivo.     

中晚期卵巢癌术后顺铂腹腔联合紫杉醇静脉化疗的临床观察

目的:观察顺铂腹腔联合紫杉醇静脉化疗治疗中晚期卵巢癌术后患者的临床疗效和安全性.方法:回顾性分析我院2006-01-2009-12行细胞减灭术Ⅱ～Ⅳ期卵巢癌76例患者,顺铂腹腔联合紫杉醇静脉化疗36例为治疗组,并以同期行顺铂联合紫杉醇静脉化疗患者40例作为对照.比较两组患者无进展生存期(PFS)、生存率和不良反应.结果:治疗组PFS 27个月,对照组PFS 23个月,P＜0.05.治疗组1、2和3年生存率分别为97.22％(35/36)、94.44％(34/36)和88.88％(32/36),对照组1、2和3年生存率分别为95.00％(38/40)、90.00％(36/40)和77.50％(31/40).治化疗组呕吐及肾功能损伤低于对照组,而腹痛高于对照组.结论:顺铂腹腔联合紫杉醇静脉化疗治疗中晚期卵巢癌术后患者可延长患者PFS及生存率,毒副反应轻,值得临床应用.     

Antitumor effect of adenovirus-mediated Bax gene transfer on p53-sensitive and p53-resistant cancer lines

Antitumor effects of the proapoptotic Bax gene have been evaluated in vitro and in vivo by a binary adenovirus system expressing the human Bax gene. Overexpression of the Bax gene in cultured cell lines from human lung carcinoma results in caspase activation, apoptosis induction, and cell growth suppression. Intratumoral injection of adenovirus vector expressing the Bar gene suppressed growth of human lung cancer xenografts established in nude mice. Histological examination of tumors from mice treated with the Bax gene demonstrated high levels of Bax expression and extensive apoptosis in tumors. In comparison with the treatment by an adenoviral vector expressing human p53, the Bax gene can effectively suppress tumor growth in both p53-sensitive and p53-resistant human lung carcinoma cell lines. Toxicity was not detected in liver and other systems in animals treated intralesionally with the Bax gene. Therefore, our results suggest that the Bar gene may be useful in cancer treatment.     

Role of p53 in the induction of cyclooxygenase-2 by cisplatin or paclitaxel in non-small cell lung cancer cell lines

Non-small cell lung Cancer (NSCLC) is extremely resistant to chemotherapeutic agents, such as cisplatin. High expression of the inflammatory enzyme Cyclooxygenase-2 (COX-2) has been shown to inhibit chemotherapy-induced apoptosis, but little is known about COX-2 regulation upon drug treatment. Recent data indicate the tumor suppressor protein p53 as an important regulator of COX-2. Therefore, TP53 status could change tumor sensitivity to chemotherapy through induction of the anti-apoptotic protein COX-2. The main objective of this work was to analyze the effect of chemotherapy on the expression of COX-2, according to TP53 status. We report herein that lung cancer cell lines expressing wild-type p53, when exposed to cisplatin treatment, induced COX-2 (mRNA and protein), with concurrent synthesis of prostaglandins (PGE₂). In contrast, COX-2 expression was not changed after cisplatin treatment of cells containing an inactive form of p53. Further, after silencing of wild-type p53 expressed in A549 cells by RNA interference, cisplatin was no longer able to induce COX-2 expression. Therefore, we suggest that induction of COX-2 by cisplatin in NSCLC cell lines is dependent on p53. For paclitaxel treatment, an increase in COX-2 mRNA expression was observed in H460 and A549 (wild-type p53 cell lines). Moreover, paclitaxel treatment increased COX-2 expression in ACC-LC-319 cell lines (p53 null), showing a p53-independent effect. These data may have therapeutic implications in the selection of patients and strategy for future COX-2 inhibition trials.     

紫杉醇联合顺铂与替吉奥联合顺铂治疗中晚期非小细胞肺癌的疗效对比研究

目的：对比分析中晚期肺癌治疗中紫杉醇与替吉奥分别联合顺铂的治疗方案的疗效差异。方法82例中晚期非小细胞肺癌中,以接受紫杉醇联合顺铂治疗的41例患者为对照组,接受替吉奥联合顺铂治疗的41例患者为观察组。对比两组近期疗效、远期疗效及不良反应发生率。结果经过4个疗程的治疗后,对照组治疗总有效率为19.51%,低于观察组的41.46%,差异有统计学意义（P﹤0.05）。随访结果显示,观察组中位生存期及中位无进展生存期分别为13.31个月及9.11个月,均高于对照组的10.83个月及8.28个月,差异有统计学意义（P﹤0.05）。此外,两组4个疗程治疗期间不良反应发生率比较,差异无统计学意义（P﹥0.05)。结论替吉奥联合顺铂治疗中晚期非小细胞肺癌相比紫杉醇联合顺铂治疗方案临床疗效及生存期更佳,且不良反应无明显增加。     

Combination chemotherapy with paclitaxel and intraperitoneal cisplatin for ovarian cancer with disseminated lesions in the peritoneum and the diaphragm

Background: In ovarian cancer, the management of micrometastases disseminated in the peritoneal cavity is extremely important. We performed intravenous paclitaxel (PAC) infusion combined with cisplatin (CDDP) intraperitoneal infusion for progressive ovarian cancer. Methods: Twelve patients with progressive epithelial ovarian cancer (FIGO IIIc), which was resected using an optimal method at primary surgery, except for disseminated lesions in the peritoneum and the diaphragm, were studied. At primary surgery, a reservoir was placed in the peritoneal cavity. If metastases were identified in the diaphragm, then another reservoir was also placed in the subdiaphragm (double reservoirs). The basic regimen was set at 175 mg/m² with divided doses of PAC and 75 mg/m² CDDP by intraperitoneal injection. When a double reservoir was used, 30 mg/m² of subdiaphragmatic CDDP and 45 mg/m² of intraperitoneal CDDP were administered. The patients received five courses of this regimen. The response to the therapy was evaluated with tumor markers, and by using cytodiagnoses on the peritoneal washing fluid collected from the reservoirs. Results: After five courses of the chemotherapy, the tumor marker levels and cytodiagnoses of all patients became negative. With reference to adverse effects, grade 3–4 neutropenia was detected in 2 patients (16.6%), peripheral neuropathy was detected in 4 patients (33.3%), and alopecia was detected in 11 patients (91.6%). The median follow-up period was 29.2 months and median progression-free survival was 25.6 months. Conclusion: The combination chemotherapy with intravenous PAC and intraperitoneal CDDP was effective on ovarian cancer with disseminated lesions in the peritoneum and the diaphragm, having only mild adverse effects. Received: February 20, 2002 / Accepted: October 9, 2002 Correspondence to:F. Terauchi     

Synergistic growth inhibition by combination of adenovirus mediated p53 transfer and cisplatin in ovarian cancer cell lines

Objective

This study was to investigate the synergistic growth inhibitory effect by combination of adenovirus mediated p53 gene transfer and cisplatin in ovarian cancer cell lines with different p53 gene mutation patterns.

Methods

Three ovarian cancer cell lines, p53 deleted SKOV3, p53 mutated OVCAR-3, and PA-1 with wild-type p53 were transduced with human adenovirus vectors carrying p53 gene (Ad-p53) and treated with a sublethal concentration of cisplatin before and after Ad-p53. The cell number was counted daily for 5 days after Ad-p53 transduction. Western blotting was used to identify p53 and p21 protein expressions, and flow cytometric analysis was performed to investigate any change of DNA ploidy after Ad-p53 transfer.

Results

Ad-p53 transduced cells successfully expressed p53 and p21 proteins after 48 hours of Ad-p53 transduction. Synergistic growth inhibition by combination of Ad-p53 and cisplatin was detected only in SKOV3 and OVCAR-3 cells, but not in PA-1 cells. In p53 deleted SKOV3 cells, cisplatin treatment after Ad-p53 showed higher growth inhibition than the treatment before Ad-p53 transduction, and reverse relationship was observed in p53 mutated OVCAR-3 cells. In SKOV3 cells, the fraction of cells at G2/M phase increased after cisplatin treatment, however, it decreased dramatically with Ad-p53 transduction.

Conclusion

The synergistic growth inhibition by combination of Ad-p53 and cisplatin may depend on the p53 status and the temporal sequence of cisplatin treatment, suggesting judicious selective application of this strategy in clinical trials.