Gemcitabine in epithelial ovarian cancer treatment: current role and future perspectives

Integrin-Mediated Targeted Cancer Therapy Using c(RGDyK)-Based Conjugates of Gemcitabine

c(RGDyK)-based conjugates of gemcitabine (GEM) with the carbonate and carbamate linkages in the 6-OH group of GEM were synthesized for the targeted delivery of GEM to integrin α_vβ₃, overexpressing cancer cells to increase the stability as well as the tumor delivery of GEM and minimize common side effects associated with GEM treatment. Competitive cell uptake experiments demonstrated that conjugate TC113 could be internalized by A549 cells through integrin α_vβ₃. Among the synthesized conjugates, TC113 bearing the carbamate linker was stable in human plasma and was further assessed in an in vivo pharmacokinetic study. TC113 appeared to be relatively stable, releasing GEM slowly into blood, while it showed potent antiproliferative properties against WM266.4 and A549 cells. The encouraging data presented in this study with respect to TC113 provide a promising keystone for further investigation of this GEM conjugate with potential future clinical applications.

Gemcitabine-induced dilated-cardiomyopathy in patient with platinum-refractory ovarian-cancer: A case report and literature review

INTRODUCTION

Gemcitabine is a nucleoside analog and pyrimidine antimetabolite that inhibits RNA synthesis, currently approved for use to treat a variety of cancers, among which ovarian cancers. Gemcitabine is considered relatively safe and it is generally well tolerated, with rarely reported cardiac side effects.

CASE REPORT

We report a case of gemcitabine induced dilated cardiomyopathy in a 41-year-old woman receiving gemcitabine as second line treatment for platinum-resistant ovarian cancer without pre-existing hypertension or significant cardiac history.Management and Outcome: The patient presented with clinical symptoms and laboratory and imaging results suggestive of congestive cardiac failure, with a left ventricular ejection fraction of 15%. Gemcitabine administration was stopped and Furosemide with ACE-inhibitors and Beta-blocker agents were initiated. At that point the clinical situation improved: symptoms and findings disappeared with gemcitabine cessation.

DISCUSSION

Our case demonstrated for the first time objective evidence for dilated cardiomyopathy induced by gemcitabine in a young patient with platinum-resistant ovarian cancer without pre-existing significant cardiac history. Although rare, gemcitabine-induced cardiotoxicity should be promptly recognized in order to take appropriate measures to manage it.

Overexpression of long noncoding RNA PTPRG-AS1 is associated with poor prognosis in epithelial ovarian cancer

OBJECTIVE Long noncoding RNAs (lncRNAs) have been shown to play a critical role in tumor progression. Abnormal expression of LncRNA PTPRG antisense RNA 1 (PTPRG-AS1) has been reported in several tumors. Hence, we aimed to determine the expression and clinical significance of PTPRG-AS1 in epithelial ovarian cancer (EOC) patients. METHODS The expressions of PTPRG-AS1 were assessed in 184 pairs of EOC tumor specimens and adjacent normal tissues. The levels of target lncRNAs and GAPDH were examined using standard SYBR-Green methods. The relationships between the expressions of PTPRG-AS1 and the clinicopathological features were analyzed using the chi-square test. Multivariate analysis using the Cox proportional hazards model was performed to assess the prognostic value of PTPRG-AS1 in EOC patients. RESULTS We confirmed that the expressions of PTPRG-AS1 were distinctly higher in the EOC tissue compared with the adjacent non-tumor specimens (p < 0.01). Higher levels of PTPRG-AS1 in EOC patients were associated with advanced FIGO stage (p = 0.005), grade (p = 0.006), and distant metastasis (p = 0.005). Survival analyses revealed that patients with high expressions of PTPRG-AS1 had a distinctly decreased overall survival (p = 0.0029) and disease-free survival (p = 0.0009) compared with those with low expressions of PTPRG-AS1. Multivariate assays indicated that PTPRG-AS1 expression was an independent prognostic factor for both overall survival and disease-free survival in EOC (Both p < 0.05). CONCLUSIONS Our study suggests that PTPRG-AS1 may serve as a novel prognostic biomarker for EOC patients.

A randomized phase II evaluation of weekly gemcitabine plus pazopanib versus weekly gemcitabine alone in the treatment of persistent or recurrent epithelial ovarian, fallopian tube or primary peritoneal carcinoma

OBJECTIVE

Angiogenesis inhibition is a valuable strategy for ovarian cancer (EOC). Pazopanib (paz) is a potent small molecular inhibitor of VEGF-1, -2, -3, PDGFR, c-kit, and has activity as a single agent in ovarian cancer. We designed a trial to assess the benefit of adding paz to gemcitabine (gem) in patients with recurrent EOC.

METHODS

An open-label, randomized, multi-site, phase 2 trial was conducted (NCT01610206) including patients with platinum resistant or sensitive disease, ≤ 3 prior lines of chemotherapy, and measurable/evaluable disease. Patients were randomly assigned to weekly gem 1000 mg/m² on days 1 and 8 of a 21 day cycle, with or without paz 800 mg QD, stratified by platinum sensitivity and number of prior lines (1 vs 2 or 3). The primary endpoint was PFS.

RESULTS

148 patients were enrolled 2012-2017. Median age was 63 years (30-82); 60% were platinum resistant; median surveillance was 13 months (0.4-54 months). Median PFS was 5.3 (95% CI, 4.2-5.8) vs 2.9 months (95% CI, 2.1-4.1) in the gem arm. The PFS effect was most pronounced in the platinum resistant group (5.32 vs 2.33 months Tarone-Ware p < 0.001). There was no difference in OS. Overall RR (PR 20% vs 11%, Chi-squre p = 0.02) and DCR (80% vs 60%, Chi-square p < 0.001) were higher in the combination. High grade AEs in the combination arm included ≥ Grade 3: hypertension (15%), neutropenia (35%), and thrombocytopenia (12%).

CONCLUSIONS

The addition of paz to gem enhanced anti-tumor activity; those with platinum-resistant disease derived the most benefit from combination therapy, even in the setting of receiving prior bevacizumab.

Inhibiting DNA Polymerases as a Therapeutic Intervention against Cancer

Inhibiting DNA synthesis is an important therapeutic strategy that is widely used to treat a number of hyperproliferative diseases including viral infections, autoimmune disorders, and cancer. This chapter describes two major categories of therapeutic agents used to inhibit DNA synthesis. The first category includes purine and pyrmidine nucleoside analogs that directly inhibit DNA polymerase activity. The second category includes DNA damaging agents including cisplatin and chlorambucil that modify the composition and structure of the nucleic acid substrate to indirectly inhibit DNA synthesis. Special emphasis is placed on describing the molecular mechanisms of these inhibitory effects against chromosomal and mitochondrial DNA polymerases. Discussions are also provided on the mechanisms associated with resistance to these therapeutic agents. A primary focus is toward understanding the roles of specialized DNA polymerases that by-pass DNA lesions produced by DNA damaging agents. Finally, a section is provided that describes emerging areas in developing new therapeutic strategies targeting specialized DNA polymerases.

Fabrication and Cytotoxicity of Gemcitabine-Functionalized Magnetite Nanoparticles

Nanotechnology has been successfully used for the fabrication of targeted anti-cancer drug carriers. This study aimed to obtain Fe₃O₄ nanoparticles functionalized with Gemcitabine to improve the cytotoxic effects of the chemotherapeutic substance on cancer cells. The (un) functionalized magnetite nanoparticles were synthesized using a modified co-precipitation method. The nanoconjugate characterization was performed by XRD, SEM, SAED and HRTEM; the functionalizing of magnetite with anti-tumor substances has been highlighted through TGA. The interaction with biologic media has been studied by means of stability and agglomeration tendency (using DLS and Zeta Potential); also, the release kinetics of the drug in culture media was evaluated. Cytotoxicity of free-Gemcitabine and the obtained nanoconjugate were evaluated on human BT 474 breast ductal carcinoma, HepG2 hepatocellular carcinoma and MG 63 osteosarcoma cells by MTS. In parallel, cellular morphology of these cells were examined through fluorescence microscopy and SEM. The localization of the nanoparticles related to the cells was studied using SEM, EDX and TEM. Hemolysis assay showed no damage of erythrocytes. Additionally, an in vivo biodistribution study was made for tracking where Fe₃O₄@Gemcitabine traveled in the body of mice. Our results showed that the transport of the drug improves the cytotoxic effects in comparison with the one produced by free Gemcitabine for the BT474 and HepG2 cells. The in vivo biodistribution test proved nanoparticle accumulation in the vital organs, with the exception of spleen, where black-brown deposits have been found. These results indicate that our Gemcitabine-functionalized nanoparticles are a promising targeted system for applications in cancer therapy.

Deoxycytidine kinase expression underpins response to gemcitabine in bladder cancer

PURPOSE

In a recent phase II clinical trial, low-dose (100 mg/m(2)) gemcitabine showed promise as a radiosensitizer in bladder cancer, but underlying mechanisms lack elucidation. Here, we investigated the mechanism of radiosensitization by low-dose gemcitabine in bladder cancer cell lines.

EXPERIMENTAL DESIGN

Four bladder cancer cell lines were screened for radiosensitization by low-dose gemcitabine using clonogenic assay, and gemcitabine-resistant RT112gem and CALgem cells created by exposure to increasing gemcitabine doses. Four key gemcitabine-regulatory genes were knocked down by transient siRNA. Nude mice carrying CALgem subcutaneous xenografts were exposed to 100 mg/kg gemcitabine ± ionizing radiation (IR) and response assessed by tumor growth delay.

RESULTS

Gemcitabine was cytotoxic in the low nanomolar range (10-40 nmol/L) in four bladder cancer cell lines and radiosensitized all four lines. Sensitizer enhancement ratios at 10% survival were: RT112 1.42, CAL29 1.55, T24 1.63, and VMCUB1 1.47. Transient siRNA knockdown of deoxycytidine kinase (dCK) significantly reduced radiosensitization by gemcitabine (P = 0.02). RT112gem and CALgem cells displayed robust decreases of dCK mRNA and protein levels; reexpression of dCK restored gemcitabine sensitivity. However, CALgem xenografts responded better to combination gemcitabine/IR than either treatment alone (P < 0.001) with dCK strongly expressed in the tumor vasculature and stroma.

CONCLUSIONS

Gemcitabine resistance in bladder cancer cell lines was associated with decreased dCK expression, but gemcitabine-resistant xenografts were responsive to combination low-dose gemcitabine/IR. We propose that dCK activity in tumor vasculature renders it gemcitabine sensitive, which is sufficient to invoke a tumor response and permit tumor cell kill in gemcitabine-resistant tumors.

Taste alterations in breast and gynaecological cancer patients receiving chemotherapy: prevalence, course of severity, and quality of life correlates

BACKGROUND

Taste alterations (TAs) are frequently reported by chemotherapy patients. However, research on this topic is very scarce. The etiologies of TAs are not fully known and prevalences may vary across tumour types and chemotherapy regimens. The aim of the present study was to longitudinally investigate TAs in patients with breast cancer or gynaecological cancers receiving chemotherapy, and to provide expected values for TAs for these patient populations.

PATIENTS AND METHODS

One hundred and nine cancer patients (32.1% gynaecological cancer, 67.9% breast cancer) receiving chemotherapy at the Department for Internal Medicine of Kufstein County Hospital were consecutively included in the study. At each visit the Quality of Life Questionnaire-Core30 and a screening scale for TAs, consisting of two validated questions taken from the European Organisation for Research and Treatment of Cancer item bank was administered. Statistical analysis was performed using mixed-effect models.

RESULTS

The prevalence of TAs in breast cancer and gynaecological cancer patients receiving chemotherapy was high (76.1%). There were differences in the extent of TAs as well as in their time course across treatment groups. The lowest TAs were found in breast cancer and gynaecological cancer patients treated with gemcitabine. The highest TAs were found in breast cancer patients treated with epirubicin/docetaxel/capecitabine. The steepest increase of TAs was found in patients treated with epirubicin/docetaxel. Moreover, significant associations between TAs and appetite loss as well as fatigue were found.

CONCLUSION

The results show that TAs are an issue in breast and gynaecological cancer patients receiving different chemotherapy regimens. There is a need for a more systematic investigation of TAs in chemotherapy patients in general as well as the need to address this issue in clinical practice.

Salvage chemotherapy for recurrent or persistent clear cell carcinoma of the ovary: a single-institution experience for a series of 20 patients

BACKGROUND

Recurrent or persistent clear cell carcinoma (CCC) of the ovary is particularly chemotherapy resistant. The purpose of this study was to review our extensive institutional experiences with recurrent or persistent CCC with the aim of finding a more effective chemotherapy regimen.

METHODS

The medical records of 67 patients treated for CCC of the ovary were retrospectively reviewed to select patients subsequently treated for recurrence or persistence of the disease.

RESULTS

The review identified 20 patients treated for recurrent or persistent CCC. For these 20 patients, 9 chemotherapeutic regimens, with 125 cycles, were administered. Gemcitabine monotherapy showed the best response rate [1 partial response (20%) and 2 stable diseases out of 5 patients so treated]. A partial response was observed with a combination of docetaxel plus irinotecan in 1 of 11 patients (9%). Stable disease was observed in 1 of 9 cases on a paclitaxel/carboplatin doublet and in 1 case on a docetaxel/carboplatin doublet. The median overall survival time was 8 months (range, 2-52). One group of patients who received gemcitabine therapy showed significantly better survival (n = 5, median 18 months) compared with a group who did not (n = 15, median 7 months) (P = 0.0108, by univariate analysis). In addition, multivariate Cox proportional hazards analysis revealed that gemcitabine administration was a significant factor for survival (hazard ratio: 13.0, 95% CI: 1.4727-115.2255, P = 0.02).

CONCLUSION

Although most chemotherapeutic regimens for recurrent or persistent CCC have little or no effect, gemcitabine showed modest activity and is the most effective agent we have tested to date.

Macrophage-capping protein as a tissue biomarker for prediction of response to gemcitabine treatment and prognosis in cholangiocarcinoma

Cholangiocarcinoma is one of the deadliest malignancies worldwide. Recent studies reported that treatment with gemcitabine was effective in prolonging survival. However, as the treatment only benefited a limited subset of patients, selection of patients before treatment is required. To discover biomarkers predictive of the response to gemcitabine treatment in cholangiocarcinoma, we examined the proteome of three types of material resource; ten cell lines, nine xenografts and nine surgically resected primary tumors from patients who exhibited different response to gemcitabine treatment. Two-dimensional difference gel electrophoresis generated quantitative protein expression profiles including 3571 protein spots. We detected 172 protein spots with significant correlation with response to gemcitabine treatment. All proteins corresponding to these 172 protein spots were identified by mass spectrometry. We found that the macrophage-capping protein (CapG) was associated with response to gemcitabin treatment in all three types of material source. Immunohistochemical validation in an additional set of 196 cholangiocarcinoma cases revealed that CapG expression was associated with lymphatic invasion status and overall survival. Multivariate analysis showed that CapG protein expression was an independent prognostic factor for overall survival. In conclusion, CapG was identified as a novel candidate biomarker to predict response to gemcitabine treatment and survival in cholangiocarcinoma.

Interstitial lung disease associated with gemcitabine treatment in patients with non-small-cell lung cancer and pancreatic cancer

PURPOSE

Although there are several reports concerning gemcitabine-induced interstitial lung disease (ILD), the risk factors for ILD are not well known. In addition, data comparing the incidence and pattern of ILD associated with gemcitabine treatment in patients with non-small-cell lung cancer (NSCLC) versus those with pancreatic cancer are scarce.

METHODS

We reviewed clinical records of 118 patients treated with gemcitabine between November 2004 and November 2010. The radiographic findings and other relevant clinical data were reviewed to identify patients who had developed ILD associated with gemcitabine treatment.

RESULTS

Out of these 118 patients, we identified 62 patients with NSCLC (group A) and 56 patients with pancreatic cancer (group B), which were then analysed. After gemcitabine administration, ILD was detected in 9 out of the total 118 patients (7.6%). Three patients had grade 2 ILD and 6 patients had grade 3 ILD. Multivariate analysis revealed that prior thoracic radiotherapy (odds ratio: 26.3) and pre-existing pulmonary fibrosis (PF) (odds ratio: 6.5) were correlated with ILD occurrence, but the incidence of ILD was not different between groups A and B. The median dose of gemcitabine administered till the manifestation of ILD tended to be lower in group A than in group B.

CONCLUSIONS

Prior thoracic radiotherapy and pre-existing PF were correlated with higher ILD rate in gemcitabine-treated patients. ILD incidence did not differ between NSCLC and pancreatic cancer patients, which may be due to the differences in treatment strategy and tumour properties.

DNA damage induced by cis- and carboplatin as indicator for in vitro sensitivity of ovarian carcinoma cells

Background

The DNA damage by platinum cytostatics is thought to be the main cause of their cytotoxicity. Therefore the measurement of the DNA damage induced by cis- and carboplatin should reflect the sensitivity of cancer cells toward the platinum chemotherapeutics.

Methods

DNA damage induced by cis- and carboplatin in primary cells of ovarian carcinomas was determined by the alkaline comet assay. In parallel, the reduction of cell viability was measured by the fluorescein diacetate (FDA) hydrolysis assay.

Results

While in the comet assay the isolated cells showed a high degree of DNA damage after a 24 h treatment, cell viability revealed no cytotoxicity after that incubation time. The individual sensitivities to DNA damage of 12 tumour biopsies differed up to a factor of about 3. DNA damage after a one day treatment with cis- or carboplatin correlated well with the cytotoxic effects after a 7 day treatment (r = 0,942 for cisplatin r = 0.971 for carboplatin). In contrast to the platinum compounds the correlation of DNA damage and cytotoxicity induced by adriamycin was low (r = 0,692), or did not exist for gemcitabine.

Conclusion

The measurement of DNA damage induced by cis- and carboplatin is an accurate method to determine the in vitro chemosensitivity of ovarian cancer cells towards these cytostatics, because of its quickness, sensitivity, and low cell number needed.

Gemcitabine pulmonary toxicity in ovarian cancer

BACKGROUND

A case of gemcitabine-induced lung toxicity is reported in a woman with stage IIIc ovarian papillary serous carcinoma.

CASE

An 83-year-old woman with stage IIIc ovarian serous papillary carcinoma diagnosed in 2001 underwent suboptimal cytoreductive surgery followed by carboplatin-paclitaxel chemotherapy. Initially in remission following chemotherapy, the disease subsequently progressed over the next 5 years. The patient received gemcitabine palliative chemotherapy. She developed significant pulmonary toxicity consistent with drug-induced interstitial pneumonitis, which improved with steroid therapy.

CONCLUSION

Gemcitabine, a second-line chemotherapy agent for the treatment of ovarian cancer, may rarely cause a serious or even fatal condition of pulmonary lung toxicity.