Determination of the mechanism of gemcitabine modulation of cisplatin drug resistance in panel of human endometrial cancer cell lines

Endometrial carcinoma complicated by malignant pericardial effusion: A case report on the therapeutic regimen

RATIONALE

High-stage endometrial carcinoma is an aggressive tumor with a high propensity for distant spread. However, metastases to the pericardium are rare in gynecological cancer, and are usually fatal.

PATIENT CONCERNS

A 69-year-old woman was diagnosed with endometrial carcinoma with pericardium metastasis. The symptoms at presentation were panic and shortness of breath.

DIAGNOSES

The cytologic examination of pericardial fluid obtained by pericardiocentesis confirmed metastasis.

INTERVENTIONS

In addition to cisplatin instilled into the pericardial space, for systemic chemotherapy, we chose that gemcitabine and lobaplatin regimen be preferred.

OUTCOMES

The patient has been participating in telephone follow-up for 8 months and has generally remained in a good condition.

LESSONS

Endometrial carcinoma can have pericardial metastases. When this happens, we recommend ultrasound-guided pericardial puncture and the pericardial injection of cisplatin, in combination with systemic chemotherapy that consists of gemcitabine and lobaplatin.

A retrospective evaluation of activity of gemcitabine/platinum regimens in the treatment of recurrent ovarian cancer

BACKGROUND

While many of these agents have been compared in prospective clinical trials, the gemcitabine/platinumbased regimens have not been compared in a prospective, randomized clinical trial. While bothgemcitabine/carboplatin and gemcitabine/cisplatin have a similar ORR in separate clinical trials, the tworegimens have never been directly been compared. With overlapping dose-limiting toxicity of thrombocytopenia, the gemcitabine/carboplatin regimen has been challenging to employ in the clinical setting in previously treated ovarian cancer patients and is often associated with treatment delays and/or dose reductions. Gemcitabine/cisplatin can also be a challenge due to its dose limiting neuropathy and renal toxicity, especially in previously treated patients. In the absence of any prospective, head to head comparison this retrospective study was embarked upon to compare the response rate and toxicity profiles of gemcitabine/cisplatin verses gemcitabine/carboplatin for the treatment of platinum-sensitive verses platinum-resistant recurrent ovarian cancer.

METHODS

This was a retrospective chart review study that identified patients that had received either gemcitabine/cisplatin or gemcitabine/carboplatin for treatment of recurrent ovarian cancer and compared documented hematological and non-hematological toxicity and response based on RECIST (v1.1). Data was evaluated based upon platinum sensitivity/resistance as well.

RESULTS

A total of 93 patients were identified that had received a gemcitabine/platinum regimen with 48 with recurrent ovarian cancer that were included in the study. There were 21 patients in the gemcitabine/cisplatin arm and 27 patients identified in the gemcitabine/carboplatin arm. Objective response rate (ORR) was greater in platinum-sensitive patients that received gemcitabine/carboplatin compared to gemcitabine/cisplatin (8 (67%) vs 2 (25%), p < 0.05). Conversely, ORR was greater in platinum-resistant patients treated with gemcitabine/cisplatin (4 (57%) vs 1 (25%), NS). Mean time to progression was greater in gemcitabine/cisplatin patients (7.2 vs 5.1 months, p < 0.03). Patients treated with gemcitabine/carboplatin discontinued due to toxicity at a greater rate (8 (33%) vs 5 (24%)). Specifically gemcitabine/carboplatin had a greater incidence (85%) of grade 2 or greater leukopenia, thrombocytopenia, and neutropenia compared to gemcitabine/cisplatin (19%) However, there was no significant difference in dose reductions, treatment delays, or granulocyte-colony stimulating factor (G-CSF) administration between regimens.

CONCLUSIONS

Gemcitabine/cisplatin appears to have greater efficacy in platinum-resistant patients, while gemcitabine/carboplatin seems to have greater efficacy in platinum-sensitive patients. Overall, gemcitabine/carboplatin was associated with a greater incidence of myelosuppression and discontinuation due to toxicity. Similar to findings in endometrial cancer, gemcitabine/cisplatin may have benefit specifically in platinum-resistant ovarian cancer.

Repression of Nrf2 enhances antitumor effect of 5-fluorouracil and gemcitabine on cholangiocarcinoma cells

Resistance to chemotherapy is the major problem in cancer treatment. Cholangiocarcinoma (CCA) is the tumor arising from the bile duct epithelium. The disease is characterized by very poor prognosis and rarely responds to current radiotherapy or chemotherapy. Transcription factor Nrf2 is activated by oxidative stress and electrophiles and contributes to cytoprotection in normal cells as well as cancer cells. Inhibition of Nrf2 can enhance the sensitivity of cancer cells to chemotherapeutic agents, although this sensitizing effect is variable depending on the cancers. In this study, we selected three CCA cell lines with different Nrf2 expression levels, detected by immunocytofluorescent staining. Chemotherapeutic agents variably induced the expression of antioxidant and xenobiotic metabolizing genes including Nrf2, NQO1, HO-1, GCLC, and GSTP1. Knockdown of Nrf2 expression by siRNA suppressed protein expression of Nrf2-regulated genes and enhanced the sensitivity to 5-fluorouracil and gemcitabine of CCA cells in both high and low basal Nrf2 expression. Cells with more resistance to chemotherapeutic agents gained more chemosensitizing effect by Nrf2 inhibition than the sensitive cells. The IC50 of the chemotherapeutic agents was also significantly reduced and the maximal cytotoxic effect was increased. Suppression of Nrf2 signaling may be a strategy to increase the efficacy of chemotherapy to CCA.

Predicting chemosensitivity to gemcitabine and cisplatin based on gene polymorphisms and mRNA expression in non-small-cell lung cancer cells

Aim: We used a panel of 17 non-small-cell lung cancer cell lines to investigate whether the presence of polymorphisms in the RRM1, ERCC1, ABCB1 and MTHFR genes and alterations in their mRNA expression can affect the in vitro chemosensitivity to cisplatin and gemcitabine. Materials & methods: Polymorphisms in these genes were evaluated by direct sequencing. mRNA expression levels were assessed by realtime PCR. In vitro chemosensitivity to cisplatin and gemcitabine was expressed as IC50 values, using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay. Results: There was a significant, positive correlation between RRM1 mRNA expression and IC50 values for gemcitabine (r = 0.6533, p = 0.0045), and there was a significant, negative correlation between ABCB1 mRNA expression and IC50 values for cisplatin (r = -0.5459, p = 0.0287). When examining the association between the polymorphisms and IC50, we found that only the MTHFR 1298A>C polymorphism showed a tendency to be more chemosensitive to gemcitabine (p = 0.0440). Conclusion: These in vitro results suggest that mRNA expression levels of the RRM1 and ABCB1 genes may be useful indicators of chemosensitivity to gemcitabine and cisplatin, respectively. The MTHFR 1298A>C polymorphism was associated with gemcitabine chemosensitivity, which require further functional analysis with co-expressed genes and should be explored in prospective clinical studies to determine its potential clinical application as a predictive biomarker.

Original submitted 11 February 2014; Revision submitted 3 November 2014

Opportunities for translation: targeting DNA repair pathways in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) remains one of the poorest prognosis neoplasms. It is typified by high levels of genomic aberrations and copy-number variation, intra-tumoural heterogeneity and resistance to conventional chemotherapy. Improved therapeutic options, ideally targeted against cancer-specific biological mechanisms, are urgently needed. Although induction of DNA damage and/or modulation of DNA damage response pathways are associated with the activity of a number of conventional PDAC chemotherapies, the effectiveness of this approach in the treatment of PDAC has not been comprehensively reviewed. Here, we review chemotherapeutic agents that have shown anti-cancer activity in PDAC and whose mechanisms of action involve modulation of DNA repair pathways. In addition, we highlight novel potential targets within these pathways based on the emerging understanding of PDAC biology and their exploitation as targets in other cancers.

Low ERCC1 expression is associated with prolonged survival in patients with bladder cancer receiving platinum-based neoadjuvant chemotherapy

PURPOSE

Excision repair cross-complementation group 1 enzyme (ERCC1) plays a key role in the removal of platinum induced DNA adducts and cisplatin resistance. Prognostic role of ERCC1 expression in the neoadjuvant setting in bladder cancer has not been reported before. We evaluated the prognostic role of ERCC1 expression in bladder cancer receiving platinum-based neoadjuvant chemotherapy.

MATERIALS AND METHODS

Thirty-eight patients with muscle invasive bladder cancer who received neoadjuvant platinum-based chemotherapy were included. Clinical and histopathologic parameters along with immunohistochemical ERCC1 staining were examined and correlated with response rates and survival.

RESULTS

Pathologic complete response rates were similar between patients with low and high ERCC1 expression. Median disease-free survival (DFS) was 9.3 vs. 20.5 months (P = 0.186) and median overall survival (OS) was 9.3 vs. 26.7 months (P = 0.058) in patients with high ERCC1 expression compared with those with low expression, respectively. In multivariate Cox regression analysis: pathological complete response (pCR) after chemotherapy (hazard ratio (HR) 0.1, 95% CI 0.012-0.842, P = 0.034) and high ERCC1 expression (HR 3.7, 95% CI 1.2-11.2, P = 0.019) were significantly associated with DFS. Patient age (>60 vs. ≤ 60 years) (HR 3.4, 95% CI 1.2-9.4, P = 0.018), the presence of pCR (HR 0.11, 95% CI 0.014-0.981, P = 0.048) and high ERCC expression (HR 6.1, 95 CI 1.9-19.9, P = 0.002) were significantly associated with OS.

CONCLUSIONS

Our results showed that high ERCC1 expression was independently associated with shorter disease-free and overall survival in patients with bladder cancer who received neoadjuvant platinum-based chemotherapy. ERCC1 may represent a potential predictive marker for platinum-based treatment in bladder cancer.

Impact of middle and lower jugular neck dissection on supraclavicular lymph node metastasis from endometrial carcinoma

Supraclavicular lymph node metastasis from endometrial carcinoma is considerably rarer than metastasis from uterine cervical cancer. To date, there have been no reported cases regarding systematic neck dissection as a salvage treatment. In this report, we describe the neck dissection procedure carried out on a 74-year-old woman with supraclavicular lymph node metastasis. Our objective was to histologically determine the origin of the metastasis while simultaneously providing appropriate treatment. The patient's past medical history included two prior cases of cancer: rectal cancer 7 years earlier and endometrial adenocarcinoma 4 years earlier. We determined that middle and lower jugular neck dissection was appropriate in treating this case based on the results of our preoperative FDG-PET and tumor markers. This surgery provided histological evidence that metastasis occurred from endometrial carcinoma. Middle and lower jugular neck dissection was expected to improve the patient's prognosis without impacting the patient's active daily life. We have continued to monitor the patient closely over an extended period.

Combination of gemcitabine and cisplatin is highly active in women with endometrial carcinoma: results of a prospective phase 2 trial

BACKGROUND

The treatment of patients with advanced or recurrent endometrial cancer remains problematic, because chemotherapy and hormonal therapy have yielded low response rates and limited progression-free survival. Because the combination of gemcitabine and cisplatin demonstrated synergism in preclinical studies, the authors attempted to determine the efficacy and toxicity of this combination in women with advanced or recurrent endometrial cancer.

METHODS

A prospective, single-institution, phase 2 study was performed in women with histologically documented International Federation of Gynecology and Obstetrics (FIGO) stage III or IV or recurrent endometrioid endometrial carcinoma. Gemcitabine at a dose of 1000 mg/m2 and cisplatin at a dose of 35 mg/m2 were administered intravenously on Days 1 and 8 of each 21-day cycle; because of myelosuppression, the protocol was revised to gemcitabine at a dose of 900 mg/m2 and cisplatin at a dose of 30 mg/m2. Patients were treated until disease progression, unacceptable toxicity, or complete response.

RESULTS

A total of 21 patients were enrolled and received a median of 5 courses of therapy (range, 1-9 courses). The median age at the time of study enrollment was 62 years (range, 41-75 years). Of 20 evaluable patients, 2 (10%) had a confirmed complete response, 8 (40%) had a partial response, 6 (30%) had stable disease, and 4 (20%) developed progressive disease. The median progression-free survival was 7.5 months (range, 2.3-33.6 months), and the median overall survival was 18.2 months (range, 2.5-49.4 months). The development of toxicity mandated dose reductions in 16 of 20 patients (80%). Eighteen patients experienced grade 3 or 4 toxic effects (graded according to the Common Terminology Criteria for Adverse Events [version 3.0]).

CONCLUSIONS

The objective response rate of 50% noted with gemcitabine and cisplatin combination chemotherapy merits the further development of this regimen in women with advanced or recurrent endometrial cancer.

Metformin reduces cisplatin-mediated apoptotic death of cancer cells through AMPK-independent activation of Akt

Metformin is an antidiabetic drug with anticancer properties, which mainly acts through induction of AMP-activated protein kinase (AMPK). In the present study we investigated the influence of metformin on the in vitro anticancer activity of the well-known chemotherapeutic agent cisplatin. Cell viability was determined by MTT and LDH release assay, oxidative stress and apoptosis (caspase activation, DNA fragmentation, and phosphatidylserine exposure) were assessed by flow cytometry, while activation of AMPK and Akt was analyzed by immunoblotting. Although metformin reduced the number of tumour cells when applied alone, it surprisingly antagonized the cytotoxicity of cisplatin towards U251 human glioma, C6 rat glioma, SHSY5Y human neuroblastoma, L929 mouse fibrosarcoma and HL-60 human leukemia cell lines. Only in B16 mouse melanoma cells metformin augmented the cytotoxicity of cisplatin. In U251 glioma cells metformin suppressed cisplatin-induced apoptotic cell death through inhibition of oxidative stress and caspase activation. The observed cytoprotection was apparently AMPK-independent, as metformin did not further increase cisplatin-induced AMPK activation in U251 cells and other pharmacological AMPK activators failed to block cisplatin-mediated apoptosis. On the other hand, metformin induced Akt activation in cisplatin-treated cells and Akt inhibitor 10-DEBC hydrochloride or phosphoinositide 3-kinase/Akt inhibitor LY294002 abolished metformin-mediated antioxidant and antiapoptotic effects. In conclusion, the antidiabetic drug metformin reduces cisplatin in vitro anticancer activity through AMPK-independent upregulation of Akt survival pathway. These data warrant caution when considering metformin for treatment of diabetic cancer patients receiving cisplatin or as a potential adjuvant in cisplatin-based chemotherapeutic regimens.

Resistance gene expression determines the in vitro chemosensitivity of non-small cell lung cancer (NSCLC)

Background

NSCLC exhibits considerable heterogeneity in its sensitivity to chemotherapy and similar heterogeneity is noted in vitro in a variety of model systems. This study has tested the hypothesis that the molecular basis of the observed in vitro chemosensitivity of NSCLC lies within the known resistance mechanisms inherent to these patients' tumors.

Methods

The chemosensitivity of a series of 49 NSCLC tumors was assessed using the ATP-based tumor chemosensitivity assay (ATP-TCA) and compared with quantitative expression of resistance genes measured by RT-PCR in a Taqman Array™ following extraction of RNA from formalin-fixed paraffin-embedded (FFPE) tissue.

Results

There was considerable heterogeneity between tumors within the ATP-TCA, and while this showed no direct correlation with individual gene expression, there was strong correlation of multi-gene signatures for many of the single agents and combinations tested. For instance, docetaxel activity showed some dependence on the expression of drug pumps, while cisplatin activity showed some dependence on DNA repair enzyme expression. Activity of both drugs was influenced more strongly still by the expression of anti- and pro-apoptotic genes by the tumor for both docetaxel and cisplatin. The doublet combinations of cisplatin with gemcitabine and cisplatin with docetaxel showed gene expression signatures incorporating resistance mechanisms for both agents.

Conclusion

Genes predicted to be involved in known mechanisms drug sensitivity and resistance correlate well with in vitro chemosensitivity and may allow the definition of predictive signatures to guide individualized chemotherapy in lung cancer.

Protein expression levels of excision repair cross-complementation group 1 and xeroderma pigmentosum D correlate with response to platinum-based chemotherapy in the patients with advanced epithelial ovarian cancer

This study was undertaken to examine whether there is an association between excision repair cross-complementation group 1 (ERCC1) and xeroderma pigmentosum D (XPD) protein expression levels and response to platinum-based chemotherapy in epithelial ovarian cancer (EOC). The study cohort consisted of 91 consecutive patients suffering from stage III or IV disease of primary EOC from 1999 to 2004 at the Women's Hospital, School of Medicine, Zhejiang University. There were 36 sensitive cases of serous ovarian cancer, 27 resistant cases of serous ovarian cancer, 15 cases of clear cell cancer, and 13 cases with serous ovarian cancer receiving neoadjuvant chemotherapy. The ovarian tissue microsections were stained by standard immunohistochemical techniques to show ERCC1 and XPD protein expression levels. In resistance group of serous ovarian cancer, ERCC1 and XPD protein expression levels were significantly higher than those of sensitivity group, and after receiving neoadjuvant chemotherapy, they showed 23% and 32% higher than before. Meanwhile, their levels of clear cell cancer group were significantly higher than serous ovarian cancer group's. Upregulation of ERCC1 and XPD protein expression was associated with resistance process to platinum-based chemotherapy in advanced EOC. This study provided evidence that differences of nucleotide excision repair-related genes expression may have an effect on the observed differences in clinical behavior of EOC.

X-linked inhibitor of apoptosis protein levels and protein kinase C activity regulate the sensitivity of human endometrial carcinoma cells to tumor necrosis factor alpha-induced apoptosis

Endometrial carcinomas are often chemoresistant. TNFalpha shows potent antitumor activity against various cancers, and if it demonstrates good antitumor activity against endometrial cancer, the cytokine could represent a valuable alternative therapeutic approach. We have tested the ability of TNFalpha to induce apoptosis in endometrial carcinoma cells, and examined a putative role for X-linked inhibitor of apoptosis protein (XIAP) in regulating cellular sensitivity to the cytokine. Exposure to TNFalpha triggered TNF-R1-dependent activation of caspases-8, -9, and -3, down-regulated Akt and XIAP proteins and induced dose-dependent and time-dependent apoptosis in Ishikawa cells. On the opposite, TNFalpha up-regulated XIAP in Hec-1A cells; in these cells, the cytokine induced delayed TNF-R1-dependent activation of caspase-8, and failed to activate caspases -9 and -3 and to induce apoptosis. However, XIAP small interfering RNA restored TNFalpha-induced caspase signaling and apoptosis in Hec-1A cells; XIAP small interfering RNA also increased TNFalpha-induced apoptosis in Ishikawa cells. In addition, inhibition of protein kinase C activity enhanced TNFalpha-induced down-regulation of XIAP and potentiated apoptosis induction, in both Ishikawa and Hec-1A cells. Finally, we found XIAP immunoreactivity in epithelial cells from a large number of human endometrial tumor tissue samples, indicating that XIAP is produced by endometrial tumor cells in vivo. This could allow XIAP to play a putative in vivo role in counteracting TNFalpha-induced apoptosis in endometrial tumor cells; in this case, direct or indirect targeting of XIAP should potentiate the antitumor effect of TNFalpha.