Clinical and preclinical activity of 2',2'-difluorodeoxycytidine (gemcitabine)

Thermosensitive polymer prodrug nanoparticles prepared by an all-aqueous nanoprecipitation process and application to combination therapy

Despite their great versatility and ease of functionalization, most polymer-based nanocarriers intended for use in drug delivery often face serious limitations that can prevent their clinical translation, such as uncontrolled drug release and off-target toxicity, which mainly originate from the burst release phenomenon. In addition, residual solvents from the formulation process can induce toxicity, alter the physico-chemical and biological properties and can strongly impair further pharmaceutical development. To address these issues, we report polymer prodrug nanoparticles, which are prepared without organic solvents via an all-aqueous formulation process, and provide sustained drug release. This was achieved by the "drug-initiated" synthesis of well-defined copolymer prodrugs exhibiting a lower critical solution temperature (LCST) and based on the anticancer drug gemcitabine (Gem). After screening for different structural parameters, prodrugs based on amphiphilic diblock copolymers were formulated into stable nanoparticles by all-aqueous nanoprecipitation, with rather narrow particle size distribution and average diameters in the 50-80 nm range. They exhibited sustained Gem release in human serum and acetate buffer, rapid cellular uptake and significant cytotoxicity on A549 and Mia PaCa-2 cancer cells. We also demonstrated the versatility of this approach by formulating Gem-based polymer prodrug nanoparticles loaded with doxorubicin (Dox) for combination therapy. The dual-drug nanoparticles exhibited sustained release of Gem in human serum and acidic release of Dox under accelerated pathophysiological conditions. Importantly, they also induced a synergistic effect on triple-negative breast cancer line MDA-MB-231, which is a relevant cell line to this combination.

Hazard assessment of antineoplastic drugs and metabolites using cytotoxicity and genotoxicity assays

Antineoplastic drugs are among the most toxic pharmaceuticals. Their release into the aquatic ecosystems has been reported, giving rise to concerns about the adverse effects, including cytotoxicity and genotoxicity, that they may have on exposed organisms. In this study, we analyzed the cytotoxicity and genotoxicity of 5-fluorouracil (5-FU) and its metabolite alpha-fluoro-beta-alanine (3-NH2-F); gemcitabine (GEM) and its metabolite 2'-deoxy-2',2'-difluorouridine (2-DOH-DiF); as well as cyclophosphamide (CP) on the HepG2 cell line. Drug concentrations were based on those previously observed in the effluent of a major cancer hospital in Brazil. The study found that GEM, 2-DOH-DiF and 5-FU resulted in reduced cell viability. No reduction in cell viability was observed for CP and 3-NH2-F. Genotoxic assessment revealed damage in the form of nucleoplasmic bridges for CP and 3-NH2-F. The tested concentrations of all compounds resulted in significantly increased MNi and NBUDs. The results showed that these compounds induced cytotoxic and genotoxic effects in HepG2 cells at concentrations found in the environment. To the best of our knowledge, this study is the first to report on the cytogenotoxic impacts of the metabolites 3-NH2-F and 2-DOH-DiF in HepG2 cells. These findings may help in the development of public policies that could minimize potential environmental contamination.

8-Methoxypsoralen Induces Apoptosis by Upregulating p53 and Inhibits Metastasis by Downregulating MMP-2 and MMP-9 in Human Gastric Cancer Cells

Furanocoumarin 8-methoxypsoralen (8-MOP) is the parent compound that naturally occurs in traditional medicinal plants used historically. 8-MOP has been employed as a photochemotherapeutic component of Psoralen + Ultraviolet A (PUVA) therapy for the treatment of vitiligo and psoriasis. Although the role of 8-MOP in PUVA therapy has been studied, little is known about the effects of 8-MOP alone on human gastric cancer cells. In this study, we observed anti-proliferative effect of 8-MOP in several human cancer cell lines. Among these, the human gastric cancer cell line SNU1 is the most sensitive to 8-MOP. 8-MOP treated SNU1 cells showed G1-arrest by upregulating p53 and apoptosis by activating caspase-3 in a dose-dependent manner, which was confirmed by loss-of-function analysis through the knockdown of p53-siRNA and inhibition of apoptosis by Z-VAD-FMK. Moreover, 8-MOPinduced apoptosis is not associated with autophagy or necrosis. The signaling pathway responsible for the effect of 8-MOP on SNU1 cells was confirmed to be related to phosphorylated PI3K, ERK2, and STAT3. In contrast, 8-MOP treatment decreased the expression of the typical metastasis-related proteins MMP-2, MMP-9, and Snail in a p53-independent manner. In accordance with the serendipitous findings, treatment with 8-MOP decreased the wound healing, migration, and invasion ability of cells in a dose-dependent manner. In addition, combination treatment with 8-MOP and gemcitabine was effective at the lowest concentrations. Overall, our findings indicate that oral 8-MOP has the potential to treat early human gastric cancer, with fewer side effects.

A lineage tree-based hidden Markov model quantifies cellular heterogeneity and plasticity

Individual cells can assume a variety of molecular and phenotypic states and recent studies indicate that cells can rapidly adapt in response to therapeutic stress. Such phenotypic plasticity may confer resistance, but also presents opportunities to identify molecular programs that could be targeted for therapeutic benefit. Approaches to quantify tumor-drug responses typically focus on snapshot, population-level measurements. While informative, these methods lack lineage and temporal information, which are particularly critical for understanding dynamic processes such as cell state switching. As new technologies have become available to measure lineage relationships, modeling approaches will be needed to identify the forms of cell-to-cell heterogeneity present in these data. Here we apply a lineage tree-based adaptation of a hidden Markov model that employs single cell lineages as input to learn the characteristic patterns of phenotypic heterogeneity and state transitions. In benchmarking studies, we demonstrated that the model successfully classifies cells within experimentally-tractable dataset sizes. As an application, we analyzed experimental measurements in cancer and non-cancer cell populations under various treatments. We find evidence of multiple phenotypically distinct states, with considerable heterogeneity and unique drug responses. In total, this framework allows for the flexible modeling of single cell heterogeneity across lineages to quantify, understand, and control cell state switching.

Single-agent gemcitabine in patients with advanced, pre-treated angiosarcoma: A multicenter, retrospective study

Gemcitabine has shown clinical activity against angiosarcoma in small series, alone, or combined with taxanes. We aimed to evaluate its activity as a single-agent in a larger series of patients with advanced angiosarcoma. We retrospectively reviewed the electronic medical records of consecutive adult patients with advanced angiosarcoma treated with single-agent gemcitabine at our institutions from January 2010 to January 2021. Response was evaluated according to RECIST 1.1, and toxicity was graded according to NCI-CTC v5.0. 42 patients were identified. 38 patients (90%) had received prior anthracyclines and weekly paclitaxel, and 9 (21%) had received pazopanib. The best tumor response was partial response (PR) in 16 patients (38%), or stable disease (10 patients, 24%). All 8 patients with cardiac angiosarcoma experienced a PR. Median PFS was 5.4 months (95%CI: 3.1-6.5), and median OS was 9.9 months (95%CI: 6.6-13.4). Single-agent gemcitabine has clinically meaningful activity in advanced, heavily pre-treated angiosarcoma.

Small Molecules and Immunotherapy Agents for Enhancing Radiotherapy in Glioblastoma

Glioblastoma (GBM) is an aggressive primary brain tumor that is associated with a poor prognosis and quality of life. The standard of care has changed minimally over the past two decades and currently consists of surgery followed by radiotherapy (RT), concomitant and adjuvant temozolomide, and tumor treating fields (TTF). Factors such as tumor hypoxia and the presence of glioma stem cells contribute to the radioresistant nature of GBM. In this review, we discuss the current treatment modalities, mechanisms of radioresistance, and studies that have evaluated promising radiosensitizers. Specifically, we highlight small molecules and immunotherapy agents that have been studied in conjunction with RT in clinical trials. Recent preclinical studies involving GBM radiosensitizers are also discussed.

Antibiotic therapy augments the efficacy of gemcitabine-containing regimens for advanced cancer: a retrospective study

BACKGROUND

The addition of antibiotics reportedly augments the efficacy of gemcitabine (GEM) in tumor-bearing mice. However, whether this phenomenon is also observed in cancer patients remains unclear. In the present study, we aimed to assess whether antibiotics for treatment or prevention of infection augments treatment efficacies of GEM-containing regimens in patients with any type of cancer.

METHODS

Medical records of patients diagnosed with cancer histopathologically and treated with GEM-containing regimens (n=169) were retrospectively reviewed. Patients were assigned into two groups: antibiotics-untreated group (patients who were treated with GEM-containing regimens but without antibiotics) and antibiotics-treated group (patients who were treated with GEM-containing regimens plus antibiotics). Response rates, progression-free survival (PFS) time, and overall survival (OS) time were analyzed for each group.

RESULTS

The response rates of the antibiotics-untreated and antibiotics-treated groups with GEM-containing regimens were 15.1% and 27.6%, respectively. The median PFS times of the antibiotics-untreated and antibiotics-treated groups were 2.5 (95% CI: 1.86-3.73) and 4.9 (95% CI: 3.47-6.0) months, respectively. The median OS times of the antibiotics-untreated and antibiotics-treated groups were 7.53 (95% CI: 5.63-9.57) months and 13.83 (95% CI: 10.83-16.43) months, respectively.

CONCLUSION

The addition of antibiotics augments the treatment efficacies of GEM-containing regimens, and it may be a potential therapeutic option to improve treatment efficacies of GEM-containing regimens in patients with advanced cancer.

Response of conventional chondrosarcoma to gemcitabine alone: a case report

Conventional skeletal chondrosarcoma is a bone neoplasm, which is poorly sensitive to anthracyclines-based chemotherapy. We report on an 18-month-long tumour response to gemcitabine as single agent in a young patient with an advanced secondary peripheral conventional chondrosarcoma, previously treated unsuccessfully with anthracyclines, ifosfamide, platinum, etoposide.

Synthesis and in vitro evaluation of novel acyclic and cyclic nucleoside analogs with a thiadiazole ring

The synthesis of six thiadiazole nucleoside analogs is reported: 5-diacetylamino-1,2,4-thiadiazol-3-one (1), 5-amino-2- (tetrahydrofuran-2-yl)-1,2,4-thiadiazol-3-one (2), 5-amino-3-[(2′-hydroxyethoxy)methyl]-1,3,4-thiadiazol-2-one (3), 5-amino-3-(4′-hydroxy-2′-hydroxymethyl-butyl)-1,3,4-thiadiazole-2-thione (4), (R)-5-amino-3-(2′,3′-dihydroxypropyl)-1,3,4-thiadiazole-2-thione (5), and (S)-5-amino-3-(2′,3′-dihydroxypropyl)-1,3,4-thiadiazole-2-thione (6). The synthesis, characterization, and properties of these new synthesized thiadiazole derivatives are discussed. A dimerization of 5-amino-3H-1,3,4-thiadiazole-2-thione (14) by sodium nitrite resulting in di-(5-amino-1,3,4-thiadiazol-2-yl) disulfide (19) is also reported. The preliminary in vitro evaluation of these newly synthesized compounds is discussed.

Gemcitabine eliminates double minute chromosomes from human ovarian cancer cells

Double minute chromosomes are cytogenetic manifestations of gene amplification frequently seen in cancer cells. Genes amplified on double minute chromosomes include oncogenes and multi-drug resistant genes. These genes encode proteins which contribute to cancer formation, cancer progression, and development of resistance to drugs used in cancer treatment. Elimination of double minute chromosomes, and therefore genes amplified on them, is an effective way to decrease the malignancy of cancer cells. We investigated the effectiveness of a cancer drug, gemcitabine, on the loss of double minute chromosomes from the ovarian cancer cell line UACC-1598. Gemcitabine is able to decrease the number of double minute chromosomes in cells at a 7500X lower concentration than the commonly used cancer drug hydroxyurea. Amplified genes present on the double minute chromosomes are decreased at the DNA level upon gemcitabine treatment. Gemcitabine, even at a low nanomolar concentration, is able to cause DNA damage. The selective incorporation of double minutes chromatin and γ-H2AX signals into micronuclei provides a strong link between DNA damage and the loss of double minute chromosomes from gemcitabine treated cells. Cells treated with gemcitabine also showed decreased cell growth, colony formation, and invasion. Together, our results suggest that gemcitabine is effective in decreasing double minute chromosomes and this affects the biology of ovarian cancer cells.

Methotrexate and gemcitabine combination chemotherapy for the treatment of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is an aggressive tumor of serosal surfaces with a poor prognosis. Methotrexate and gemcitabine have exhibited single-agent activity in MPM. We evaluated the feasibility of sequential administration of these agents in the treatment of MPM. A total of 21 patients with MPM received a 30-min infusion of 100 mg/m² methotrexate and, 30 min later, a 30-min infusion of 800 mg/m² gemcitabine. Twenty-four hours following the administration of methotrexate, leucovorin rescue therapy was initiated (10 mg/m² leucovorin administered 4 times at 6-h intervals). These treatments were administered weekly, with 4 weekly administrations constituting a cycle of therapy. A total of 88 cycles were administered to the 21 patients, with each patient receiving 1-10 cycles (median, 4.2 cycles). Eight patients (38.1%) exhibited a partial response, 10 patients (47.6%) had stable disease and 3 patients (14.3%) had progressive disease. The median overall survival was 19.4 months (range, 02-41 months). One-year and 2-year survival rates were 61.9 and 38.1%, respectively. Hematological toxicity was considered acceptable, with grade 3-4 toxicities occurring in 3 (14.3%) patients. Non-hematologic toxicity was generally mild. There was no treatment-related mortality. Our results suggest that methotrexate and gemcitabine combination therapy is feasible and effective in the treatment of MPM. This regimen may offer an alternative to platinum-based chemotherapy and a prospective trial including a larger cohort of patients is recommended to confirm these results.

Improved plasma stability and sustained release profile of gemcitabine via polypeptide conjugation

To enhance the stability of the anticancer drug gemcitabine (2'-deoxy-2',2'-difluorocytidine), it was conjugated to poly-l-glutamic acid (PG-H) via a carbodiimide reaction. The synthesised poly-l-glutamic acid-gemcitabine (PG-G) was purified and characterised by using SDS-PAGE to estimate its molecular weight, HPLC to determine its purity and degree of drug loading, and NMR to elucidate the structure. In vitro aqueous hydrolytic studies showed that the gemcitabine release from the polymeric drug conjugate was pH dependent, and that the conjugation to PG-H improved its stability in human plasma. The release of the bound gemcitabine from PG-G in plasma was mediated by a hydrolytic process. It began with a lag phase, followed by linear release between 12 and 48h, and reached equilibrium at 72h with 51% of the gemcitabine released. In vitro cytotoxicity studies using MCF-7 and MDA-MB-231 human mammary cancer cells, as well as human dermal fibroblasts (HDF), showed that PG-G displayed a lower dose dependent cytotoxic effect with respect to the parent drug gemcitabine. On the other hand, in 4T1 mouse mammary tumour cells, PG-G and gemcitabine showed similar toxicities. Gemcitabine was more than likely released hydrolytically from PG-G and taken up by MCF-7, MDA-MB-231 and HDF, whereas both released gemcitabine and PG-G were taken up by 4T1 to mediate the observed cytotoxicities. The improved stability and extended sustained release profile may render PG-G a potential anticancer prodrug.

In situ protein expression of RRM1, ERCC1, and BRCA1 in metastatic breast cancer patients treated with gemcitabine-based chemotherapy

Ribonucleotide reductase 1 (RRM1) is a determinant of gemcitabine efficacy in non-small-cell lung cancer and pancreatic cancer. We investigated the protein levels of RRM1 and two other DNA repair enzymes, ERCC1 and BRCA1, in 55 metastatic breast cancer (MBC) patients undergoing gemcitabine-based chemotherapy. With automated in situ protein quantification (AQUA v1.6), the average scores for RRM1, ERCC1, and BRCA1 ranged from 245.6-2774.1, 74.0-410.3, and 54.4-1833.1, respectively. They were significantly associated with each other (Spearman's rho > or = .36; p < or = .007). Given their pattern of distribution, RRM1 and BRCA1 are potentially suitable markers for clinical decision making in MBC.

Phase II study of fixed dose rate gemcitabine as radiosensitizer for newly diagnosed glioblastoma multiforme

PURPOSE

In order to evaluate the activity of gemcitabine as radiosensitizer for newly diagnosed glioblastoma multiforme (GBM), a prospective single-center phase II study was conducted.

METHODS

Eligible patients were required to have histologically proven GBM with evaluable and/or measurable disease after surgery. They were treated by standard cranial irradiation plus concomitant fixed dose rate gemcitabine given intravenously at 175 mg/m(2) weekly for 6 weeks. After chemo-radiotherapy, irrespective of tumor response, patients went on to receive oral temozolomide at 150-200 mg/m(2) for 5 days every 28 days.

RESULTS

Twenty-three patients were enrolled. Median age was 57 years (range 43-72) and median Karnofsky performance status was 90 (range 70-100). Seventeen patients had received subtotal resection of the tumor, while six patients had biopsied-only tumors. Four patients responded to treatment (17.5%) with additional 14 (61%) experiencing stable disease for an overall disease control rate of 78.5%. Median progression-free and overall survival were 6.8 and 10.1 months, respectively. The concomitant radiotherapy-gemcitabine combination was well tolerated and severe adverse events were rare, consisting of grade 3 neutropenia and hypertransaminasemia in two cases each. Twenty patients were assessable for methylguanine methyltransferase (MGMT) promoter methylation, 11 of which were found methylated. In the methylated and unmethylated cohorts, disease control was obtained in 10/11 patients (91%) and 7/9 patients (77.5%), respectively.

CONCLUSIONS

Concomitant radiotherapy-gemcitabine is active and well tolerated in newly diagnosed glioblastoma multiforme. Activity is observed both in tumors with methylated and unmethylated MGMT promoter.

Gemcitabine combined with oxaliplatin in pretreated patients with malignant pleural mesothelioma: an observational study

Background

The aim of this study was to investigate the efficacy and safety of oxaliplatin ± gemcitabine in patients with diffuse malignant pleural mesothelioma (MPM) pretreated with pemetrexed.

Methods

The study enrolled consecutive patients with relapsed MPM, all of them pretreated with a platin-pemetrexed-based chemotherapy. Oxaliplatin 80 mg/m² was administered as monotherapy or in combination with gemcitabine 1000 mg/m² given on day 1 and 8. Cycles were repeated every 21 days. The primary endpoints were response rate and disease control rate. Secondary endpoints included overall survival (OS), time to tumour progression (TTP), progression-free survival (PFS), time to treatment failure (TTF), and toxicity.

Results

Between February 2005 and September 2007 29 patients (median age: 65.0 years, World Health Organisation (WHO) performance status: 0–3) were enrolled. The follow-up period encompassed 5.4 to 97.4 weeks (median: 24.3 weeks). Out of these 29 patients, 15 were treated in second, 10 in third, 3 in fourth and 1 in fifth line, respectively. The majority of the patients received the combination oxaliplatin and gemcitabine (n = 25 vs. 4; 86.2 vs. 13.8%).

The median overall survival (OS) was 71.7 weeks (30.6–243.3 weeks), whereas survival from the start of oxaliplatin/gemcitabine-treatment was 24.3 weeks (5.4–97.3 weeks). Median time to tumour progression (TTP) was 9.3 weeks (3.0–67.6 weeks).

Partial response (PR) was observed in 2 patients (6.9%), stable disease (SD) for at least three courses of treatment in 11 patients (37.9%). Thus, disease control rate was 44.8%, whereas 16 of 29 patients exhibited progressive disease (55.2%).

The toxicity profile was favourable, with no WHO grade 4-toxicities, only few dose-reductions were performed due to non-symptomatic haematotoxicities (neutropenia, thrombopenia). Mild WHO grade 2 neurotoxicity was seen in 6 patients.

Conclusion

Pemetrexed-pretreated patients with progressive MPM may benefit from a consecutive chemotherapy with oxaliplatin and gemcitabine without significant toxicity.

Treatment of recurrent or persistent platinum-refractory ovarian, fallopian tube or primary peritoneal cancer with gemcitabine and topotecan: a phase II trial of the Puget Sound Oncology Consortium

OBJECTIVE

To determine the nature and degree of toxicity, response rate, quality of life (QOL), and progression-free interval in women with platinum-resistant refractory ovarian or peritoneal cancer receiving weekly topotecan and gemcitabine.

METHODS

A Phase II trial of gemcitabine 800 mg/m(2) and topotecan 3.0 or 2.5 mg/m(2) administered on days 1 and 8 of a 21-day cycle was conducted. Response was assessed by RECIST criteria. Quality of life was assessed with FACT-O.

RESULTS

Twenty-three patients were enrolled in the study and all were evaluable. One patient was later found to be ineligible due to a concurrent endometrial malignancy, but remains part of the analysis. Sixteen patients (70%) had measurable disease at baseline and 7 (30%) had elevated CA125 only. The median number of prior regimens was 1, range 1-4 and median number of prior cycles was 8, range 3-39. The first 6 patients received topotecan at a dose of 3.0 mg/m(2), but because of dose delays and need for GCSF the dose of topotecan was lowered to 2.5 mg/m(2). There were 4 (17%) partial responses, but only two (9%) were confirmed prior to progression; and 8 (35%) had stable disease. Toxicity was acceptable with only 8 of the 107 cycles given requiring a dose reduction. Four patients (17%) were taken off the study for toxicity, two at the higher dose and two at the lower dose. Median time to recurrence was 3.0 months and median overall survival was 12.6 months. QOL did not differ with subsequent cycles as compared to baseline.

CONCLUSION

The combination of weekly topotecan and gemcitabine is well tolerated, but best response rate is 17%, and confirmed response is only 9%, which is not significantly better than single agent gemcitabine or topotecan. These results do not provide compelling evidence for the combination of weekly gemcitabine and topotecan as a promising therapy.

Intraperitoneal gemcitabine pharmacokinetics: a pilot and pharmacokinetic study in patients with advanced adenocarcinoma of the pancreas

BACKGROUND

The pyrimidine analogue gemcitabine (2', 2'-difluorodeoxycitidine, dFdC) is active against pancreatic cancer, and its high clearance (CL(tb)) and low incidence of local toxicity make it an excellent candidate for evaluation as intraperitoneal (IP) therapy. We designed a dosing schema that used multiple sequential exchanges of a peritoneal dialysate containing dFdC in an effort to produce prolonged IP dFdC exposure.

METHODS

As part of a study involving multi-modality therapy for advanced pancreatic adenocarcinoma, patients were treated with four 6-h IP dwells of dFdC (50 mg/m(2) in 2 l) over a 24-h period. A second 24-h cycle of IP dFdC therapy was repeated 1 week later. Each exchange of dialysate contained 50 mg/m(2) dFdC in 2 l of commercial 1.5% dextrose dialysis solution. Plasma and peritoneal fluid were analyzed by HPLC to determine concentrations of dFdC and its inactive metabolite 2', 2' difluorodeoxyuridine (dFdU). Clinical data were recorded to note drug toxicity and response.

RESULTS

Nine patients underwent IP dFdC therapy, and eight were able to receive two cycles. There were no recorded significant toxicities. Low plasma dFdC concentrations (<1 microg/ml) were present transiently in seven of nine patients, and dFdC was not detectable in the plasma of the other two. Plasma dFdU concentrations were low but increased gradually until 12 h and then declined little if any. IP dFdC concentrations declined rapidly, and dFdC was seldom measurable prior to administration of the next scheduled 6-h dwell. dFdU concentrations in peritoneal fluid were very low (<0.5 microg/ml) throughout treatment. The mean area under the concentration versus time curve (AUC) for dFdC in peritoneal fluid was 182 microg/ml x h, which was approximately 70x the AUC of dFdC reported in the ascites of a patient undergoing systemic dFdC therapy.

CONCLUSIONS

IP dFdC was well tolerated, and no significant toxicities were noted. The rapid decrease in peritoneal dFdC concentrations and low concentrations of IP dFdU imply almost total absorption of IP-administered dFdC. Little, if any, dFdC could be detected in plasma, but the steady-state plasma dFdU concentrations also imply absorption and inactivation of virtually all IP-administered dFdC. These findings are consistent with the known high CL(tb) and low incidence of local toxicity of dFdC and argue for its further evaluation as a drug for IP therapy.

Rationale and appropriate use of chemotherapy and radiotherapy for pancreatic ductal adenocarcinoma

The emergence of effective systemic chemotherapy, along with the parallel development of new targeted cell signal inhibitors for pancreatic cancer treatment, has provided impetus for a re-examination of the appropriate use of chemotherapy and radiation therapy in this malignancy. In addition to exciting developments in the treatment of locally advanced and metastatic disease, new data have emerged regarding the efficacy of adjuvant and neoadjuvant therapy when combined with traditional surgical approaches such as a Whipple procedure. This review summarizes the sentinel clinical trials and discoveries that have influenced the development and deployment of scientifically based multidisciplinary care for today's patients, with a particular focus on modern radiation and chemotherapy.

Optimizing gemcitabine regimens in ovarian cancer

Ovarian cancer represents the leading cause of death from gynecologic neoplasms. The chance of response to secondary treatment is currently disappointing; few agents have shown notable activity in recurrent/progressive patients. Among these agents, gemcitabine represents one of the most interesting newer antineoplastic agents, showing significant activity, synergism with cisplatin, and a mild toxicity profile in both platinum-sensitive and platinum-resistant (and also taxane-pretreated) recurrent/progressive patients. Moreover, first-line combination chemotherapy including gemcitabine has shown promising response rates in phase I and II studies. The ongoing phase III, five-arm, randomized Gynecologic Oncology Group Protocol 182/International Collaborative Ovarian Neoplasm 5 study should clarify the clinical impact of the addition of a third drug to the standard paclitaxel plus carboplatin treatment regimen.

Role of gemcitabine in cancer therapy

Gemcitabine, a pyrimidine nucleoside antimetabolite, is one of the most promising new cytotoxic agents. The drug has shown activity in a variety of solid tumors, and has been approved for the treatment of non-small cell lung cancer, pancreatic, bladder, and breast cancer. Recent data showed that gemcitabine is also active against ovarian cancer. Gemcitabine has a good toxicity profile, with myelosuppression being the most common side effect, while non-hematological events are relatively uncommon. The low toxicity profile makes the drug a valid option for unfit and elderly patients. Due to the synergistic activity with other chemotherapeutic compounds, mainly cisplatinum, several trials have been conducted to evaluate the efficacy and tolerability of gemcitabine in combination with other cytotoxic agents. Current clinical trials are evaluating the role of gemcitabine in combination with new targeted therapies.

Development of gemcitabine in non-small cell lung cancer: the Italian contribution

Gemcitabine, a pyrimidine nucleoside antimetabolite, is one of the most promising new cytotoxic agents. The drug has shown activity in a variety of solid tumors, but appears to be most active in the treatment of non-small cell lung cancer. In this disease, several Italian investigators have evaluated gemcitabine in phase II and III clinical trials. Due to preclinical synergism with cisplatin, the Italian Lung Cancer Project played an important role to assess the efficacy and activity of the gemcitabine-cisplatin combination along with the best doses and schedule to adopt, thus leading to gemcitabine approval for first line treatment of advanced non-small cell lung cancer. Several Italian studies have also investigated gemcitabine non-platinum based combinations, gemcitabine in third generation platinum-based triplets and gemcitabine as second line therapy, but all these studies led to conflicting and inconclusive results. The low toxicity profile makes the drug a valid option for unfit and elderly patients. The Multicenter Italian Lung Cancer in the Elderly Study was a phase III randomized trial conducted in elderly patients with advanced non-small cell lung cancer that showed that single agent gemcitabine is at least as effective as either single agent vinorelbine or the combination of gemcitabine and vinorelbine. In the neoadjuvant treatment of stage III disease, a number of phase II studies with third generation platinum-based doublets or triplets have been conducted by Italian investigators with encouraging results. Current clinical trials are addressing the role of gemcitabine in combination with new targeted therapies. Future studies should be designed in order to identify subgroups of patients who are more likely to benefit from gemcitabine chemotherapy.

Phase II study of gemcitabine in children with relapsed acute lymphoblastic leukemia or acute myelogenous leukemia (ADVL0022): a Children's Oncology Group Report

BACKGROUND

To determine the response rate and toxicity to gemcitabine administered as 10 mg/m2/min x 360 min weekly for 3 weeks in children with relapsed acute lymphoblastic leukemia (ALL) or acute myelogenous leukemia (AML). Gemcitabine is a deoxycytidine analog that inhibits DNA synthesis and repair and has a broad spectrum of antitumor activity.

PROCEDURE

From April 2001 to April 2003, 23 male and 9 female eligible patients were recruited for the Children's Oncology Group (COG) phase II study of Gemcitabine (ADVL0022).

RESULTS

One of 20 evaluable patients with ALL and none of 10 evaluable patients with AML had complete responses to gemcitabine; there were no partial responses. Grade 3 or 4 hematologic toxicity and liver toxicity were common during therapy. Only one patient was alive 1 year after entry. The estimated 1-year overall survival probability for the 32 patients was 4% (SE = 3%).

CONCLUSIONS

Gemcitabine at the dose and schedule in this trial was not effective for children with relapsed AML or ALL.

Monitoring of cell growth and assessment of cytotoxicity using electrochemical impedance spectroscopy

Electrochemical impedance spectroscopy (EIS) was used to monitor the growth of mammalian cancer cells and evaluate the cytotoxicity of chemicals using Fe(CN)6(3-/4-) as a redox probe. Cancer cells, the human hepatocarcinoma cell line (BEL7404), were grown on optically transparent indium tin oxide (ITO) semiconductor slides, which were used as the working electrodes in electrochemical experiments. Attachment and proliferation of cancer cells on ITO surfaces resulted in increase of electron-transfer resistance (R(et)) between the redox probe of Fe(CN)6(3-/4-) in electrolyte solution and ITO electrode surface. For cytotoxicity assessment, cells grown on ITO substrates were further cultured in the presence of different cytotoxicants and electrochemical impedance measurements were carried out at different time intervals. Gemcitabine, a promising antineoplastic drug showing activity against a wide spectrum of human solid tumors, was selected as a model for long-term cytotoxicity effect study, whereas mercury chloride represented a model for acute toxicants. The inhibitions of gemcitabine and mercury chloride on the viability and proliferation of BEL7404 cells were observed from the electrochemical impedance experiments, and the different action modes were discriminated. Additionally, microscope images were also used to observe the effects of these two chemicals on the morphology of the cells. General consistency has been found between the electrochemical impedance response and the morphological observation. Such an impedance method provides a simple and inexpensive way for in vitro assessment of chemical cytotoxicity.

Preclinical relevance of dosing time for the therapeutic index of gemcitabine-cisplatin

The relevance of gemcitabine timing for chronotherapeutic optimisation was investigated. Healthy mice received multiple doses of gemcitabine (120, 160 or 200 mg kg⁻¹ injection (inj)⁻¹) at one of six circadian times (3, 7, 11, 15, 19 or 23 h after light onset – HALO) on days 1, 4, 7 and 10 or a single dose of gemcitabine (400 mg kg⁻¹) at 11 or 23 HALO±cisplatin (5 mg kg⁻¹ at 1 min, 4 or 8 h later). Mice bearing Glasgow osteosarcoma received multiple doses of gemcitabine (200 mg kg⁻¹ inj⁻¹) at 11 or 23 HALO±cisplatin (5 mg kg⁻¹ inj⁻¹ at 1 min or 4 h later) on days of 10, 13, 16 and 19 following tumour inoculation. A circadian rhythm in body weight loss was statistically validated, with 1030 HALO corresponding to the least toxic time (95% CL, 0800 to 1300). Gemcitabine dosing produced least body weight loss and least neutropenia after injection at 11 vs 23 HALO, whether the drug was given alone or with cisplatin (P=0.001). Gemcitabine–cisplatin tolerability was improved by dosing gemcitabine at 11 HALO and CDDP at 15 HALO (P<0.001). The administration of this schedule to tumour-bearing mice increased median survival three-fold as compared to treatments where both drugs were given simultaneously at 11 or 23 HALO (P=0.02). The optimal schedule would correspond to the delivery of gemcitabine upon awakening and cisplatin near mid-activity in cancer patients.

Retrospective analysis of adverse drug reactions induced by gemcitabine treatment in patients with non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the leading cause of cancer death in the world. Traditional chemotherapy for advanced NSCLC is often considered excessively toxic. Recent clinical trials documented that gemcitabine may represent a good therapeutical option in patients with NSCLC. Aim of our research was to retrospectively evaluate the adverse effects induced by gemcitabine in patients with NSCLC from 1 January 1997 to 31 December 2002, in clinical records of Oncology Divisions of "S. Giovanni di Dio" Hospital of Crotone, "Ospedali Riuniti" Hospital of Reggio Calabria, Hospital of Paola, and in Pneumological Oncology Division of "Mariano Santo" Hospital of Cosenza, Italy. Clinical records of patients treated with gemcitabine (1000mgm(-2) on days 1 and 8) were reviewed and following data were obtained: sex and age of the patients, histologic diagnosis and disease stage, World Health Organisation (WHO) performance status and toxic effects induced by gemcitabine. We reported that 71.6% of NSCLC patients (age range 48-77 years; 135 males, 27 females; performance status 0=53, 1=109) were eligible for our study. Side effect of gemcitabine involved gastrointestinal system (nausea, vomiting and diarrhoea) and only in the last cycles (VIII-XI) emopoiethic system (leukopenia, neutropenia, thrombocytopenia and anemia). Grade IV vomiting occurred in three patients, thrombocytopenia in two. Grade III leukopenia was observed in three patients. Other toxicities were mild. None of the patients died during chemotherapy. In conclusion, these data showed that gemcitabine present a very good tolerability in patients with NSCLC. Therefore, it could be considered as a new therapeutic agents to use as first line therapy for this disease.

A Phase I Dose Escalation Trial of Gemcitabine with Radiotherapy for Breast Cancer in the Treatment of Unresectable Chest Wall Recurrences

The purpose of this study was to determine the maximum tolerated dose (MTD) of gemcitabine when given concurrently with standard radiotherapy for the treatment of chest wall recurrences, and to compare actuarial rates of local-regional control with those achieved in historical controls. Patients with unresectable chest wall recurrences were enrolled in a phase I trial of concurrent gemcitabine and radiotherapy. Gemcitabine was increased at 150 mg/m(2)/week increments, starting at 300 mg/m(2)/week. Radiotherapy was delivered to the chest wall and regional nodes to a total of 60 to 70 Gy in 2 Gy daily fractions. Treatment toxicity was assessed and a comparison of treatment outcome was performed between study patients and historical groups treated with either radiotherapy alone or excision followed by radiotherapy. The dose-limiting toxicities of neutropenia and thrombocytopenia occurred at the second planned dose of 450 mg/m(2)/week after accrual of only six patients, resulting in a MTD of 300 mg/m(2)/week. Myelosuppression and skin desquamation were commonly observed. Actuarial rates of local-regional control were 100%, 50%, and 90% at 2 years for the gemcitabine with radiotherapy, radiotherapy alone, and excision followed by radiotherapy groups, respectively (p = 0.105). The difference among the Kaplan-Meier curves for overall local-regional control was statistically significant at p = 0.007 in favor of combined gemcitabine and radiotherapy. The MTD of gemcitabine is 300 mg/m(2)/week when gemcitabine is delivered concurrently with radiotherapy for unresectable chest wall failures. This novel approach suggests excellent local-regional control when compared to historical controls. A phase II trial is warranted.

New agents in the treatment of small-cell lung cancer: focus on gemcitabine

Small-cell lung cancer (SCLC) accounts for 20%-25% of all new cases of lung cancer and represents the sixth most commonly diagnosed cancer in the United States. Given the tumor's systemic nature and chemoresponsiveness, chemotherapy has become the cornerstone of its management. Chemotherapy significantly prolongs survival; however, most of the patients still die within 2 years of diagnosis. Combination chemotherapy represents the treatment of choice for this disease. In the United States, cisplatin/etoposide is the regimen most frequently used for the first-line therapy of SCLC patients because of its better therapeutic index. Upon recurrence, topotecan is the Food and Drug Administration-approved treatment based on a phase III trial that showed no statistically significant differences in survival or response for topotecan compared with CAV (cyclophosphamide/doxorubicin/vincristine) but a better disease-related symptom improvement compared to baseline favoring the topoisomerase I inhibitor. Newer agents, with novel mechanisms of action, have shown activity against SCLC and are being tested in many different combinations. Among these agents, gemcitabine has attractive mechanisms of action and toxicity profile. Gemcitabine is a pyrimidine nucleoside antimetabolite, analogue to cytosine arabinoside, which through incorporation into the DNA leads to inhibition of DNA synthesis and cytotoxicity. As a single agent, gemcitabine has modest activity against SCLC. However, like with many other drugs, response rates improve when gemcitabine is used in combination regimens. Phase II and III studies of combinations with classic drugs for the management of SCLC patients such as cisplatin and/or etoposide and gemcitabine demonstrate comparable results to those of standard therapies. The gemcitabine/paclitaxel and gemcitabine/topoisomerase I inhibitor combinations are also of great interest, and preliminary results in previously treated patients are promising. The proper role of gemcitabine in the treatment of patients with SCLC awaits future testing in randomized phase III trials.

A 21-day schedule of gemcitabine and cisplatin administration in the treatment of advanced non-small cell lung carcinoma: a phase II study

PURPOSE

To evaluate the efficacy and toxicity of gemcitabine and cisplatin combination chemotherapy, we conducted a phase II study of this regimen in patients with advanced non-small cell lung carcinoma (NSCLC).

MATERIALS AND METHODS

From June 2001 to August 2003, 36 chemotherapy-naive patients with stage IIIB or IV NSCLC were enrolled. The median age was 59 years (range, 42 to 75 years), and performance status was 0 or 1. Eleven patients had stage IIIB disease, and 25 patients had stage IV disease. 1,000 mg/m(2) of gemcitabine was administered on day 1 & 8, and 60 mg/m(2) of cisplatin was administered on day 1. Each cycle was repeated every 21 days.

RESULTS

Everyone subject who participated were assessable. A total of 160 cycles of chemotherapy were delivered, and the median number of chemotherapy courses was 3.5 (range, 2 to 9). Two patients (5.6%) achieved a complete response, and 14 patients (38.9%) achieved a partial response. The overall response rate was 44.5% (95% confidence interval [CI], 32.5 to 56.5%). The median follow-up duration was 9.3 months. The median time to disease progression was 8.6 months (95% CI 7.4 to 9.9 months), and median survival time was 12.2 months (95% CI, 10.5 to 12.9 months). Grade 3/4 neutropenia occurred in 9 patients (25.0%), neutropenic fever occurred in 3 patients (8.3%), and grade 3/4 thrombocytopenia occurred in 7 patients (19.5%). Mild forms of non-hematologic toxicities, such as nausea, vomiting or skin reactions, were observed.

CONCLUSION

The combination of gemcitabine and cisplatin in a 21-day schedule is an effective regimen for patients with NSCLC in its advanced stages.

Mistletoe and gemcitabine in patients with advanced cancer: a model for the phase I study of botanicals and botanical-drug interactions in cancer therapy

Plant extracts of the European mistletoe (MTE), Viscum album, the most widely used cancer treatment in Germany, have been used in European countries as sole intervention or as adjunct to conventional cancer therapies for more than 80 years. Preclinical data suggest immunostimulatory and cytotoxic effects of MTE. While the clinical efficacy of MTE in cancer is being investigated, toxicity and potential interactions of MTE with standard chemotherapeutic agents are unknown. Gemcitabine is an approved antimetabolite chemotherapeutic agent effective as single agent in patients with solid tumors (ST). The documented metabolism and pharmacokinetics of gemcitabine make this agent well suited for the study of botanical-chemotherapy drug interactions (BDIA) in cancer. Based on reports of altered drug metabolism associated with botanical preparations, research into BDIA has intensified. The phase I, 2-stage, dose-escalation study outlined here will test MTE with gemcitabine as a paradigm for the phase I investigation of botanical-drug combination treatments in patients with advanced ST. The protocol including the following components has been reviewed and approved by the National Cancer Institute Institutional Review Board (IRB), the National Naval Medical Center IRB, and the Navy Clinical Investigation Program (study 02-074): (1) use of a standardized MTE, approved by the Food and Drug Administration for investigational use; (2) independent verification of key MTE components considered biologically active; (3) identification of contaminants and adulterants; (4) pharmacokinetics of gemcitabine and its principal metabolites before and upon exposure to MTE; (5) safety and toxicity data collection; (6) assays of plasma ML antibody production in vivo; and (7) pharmacodynamic studies of the botanical-drug combination.

Gemcitabine Plus Vinorelbine Chemotherapy in Patients with Advanced Bladder Carcinoma Who Are Medically Unsuitable for or Who Have Failed Cisplatin-Based Chemotherapy

OBJECTIVE

To evaluate the efficacy and toxicity of gemcitabine plus vinorelbine chemotherapy in patients with advanced bladder carcinoma who are unsuitable for or who have failed cisplatin-containing chemotherapy.

PATIENTS AND METHODS

Thirty-one patients with advanced transitional cell carcinoma (TCC) of the bladder were scheduled to receive gemcitabine and vinorelbine chemotherapy. Twenty-one patients had received no prior chemotherapy and their creatinine clearance was below 50 ml/min (group 1), and the remaining 10 patients did not respond to previous cisplatin-containing chemotherapy (group 2).

RESULTS

In group 1, objective response rate was 47.6%, including 2 (9.5%) complete and 8 (38.9%) partial responses. In group 2, partial response was observed in 2 (20%) patients. The median survival time for patients in group 1 and 2 were 15 months (range 3-23) and 7 months (range 3-21), respectively. Grades 3 or 4 leukopenia developed in 16.1% of patients. Overall, 12.9% of the patients suffered from grade 3 nonhematologic toxicity.

CONCLUSION

Our preliminary data indicate that the combination of gemcitabine and vinorelbine is active and well tolerated especially in patients with advanced TCC who are unsuitable for cisplatin-based chemotherapy.

A new multidrug reinduction protocol with topotecan, vinorelbine, thiotepa, dexamethasone, and gemcitabine for relapsed or refractory acute leukemia

We report the results of a phase 2 nonrandomized single-arm trial of a combination therapy for relapsed or refractory leukemia. From January 1999 to June 2002, 28 patients with multiple relapsed or refractory acute leukemia received a combination of topotecan, vinorelbine, thiotepa, dexamethasone, and, for patients with an M3 marrow on day 7, gemcitabine. A total of 14 patients had pre-B-ALL (acute lymphoblastic leukemia), three had T-cell leukemia, nine acute myeloblastic leukemia (AML), and two biphenotypic leukemia. In all, 13 patients achieved a significant response (10 complete responses and three partial responses). Among the responders, five had pre-B-ALL, two had T-cell leukemias, five had AML, and one had biphenotypic leukemia. In total, 10 of these patients subsequently underwent hematopoietic stem cell transplantation, and four are alive without disease. One patient died, while in remission, of complications resulting from an episode of sepsis and pneumonia that occurred during topotecan, vinorelbine, thiotepa, dexamethasone, and gemcitabine (TVTG) reinduction. Other toxicities included grade 4 neutropenia in all patients and transient grade 2 hepatotoxicity in 10 patients (36%). In summary, we report that 47% of heavily pretreated pediatric patients with multiply relapsed or refractory leukemia achieved a significant response after therapy on the TVTG protocol. Further studies are warranted to evaluate the role of the TVTG combination in the treatment of leukemia.

Treatment of recurrent platinum resistant ovarian or peritoneal cancer with gemcitabine and doxorubicin: A phase I/II trial of the Puget Sound Oncology Consortium (PSOC 1602)

OBJECTIVE

This study was undertaken to determine the degree of toxicity, response rate, and evaluate quality of life (QOL) in women receiving gemcitabine in combination with doxorubicin for platinum-resistant and refractory ovarian or peritoneal cancer.

STUDY DESIGN

This was a phase I/II prospective trial.

MATERIALS AND METHODS

Nine patients were enrolled in the phase I portion. Initial doses of gemcitabine, 800 mg/m(2) intravenously on days 1, 8, and 15, and doxorubicin, 25 mg/m(2) intravenously on days 1, 8, and 15 in a 28-day cycle resulted in dose limiting toxicity secondary to thrombocytopenia and neutropenia. Forty patients were treated on the phase II portion with gemcitabine, 700 mg/m(2) intravenously on days 1 and 8, and doxorubicin 20 mg/m(2) intravenously on days 1 and 8 with granulocyte colony-stimulating factor administered on days 2 to 7 and 9 to 14 in a 21-day cycle. QOL was assessed with Fact-O.

RESULTS

The median number of previous chemotherapy regimens for the 49 women was 2 (range 1-5). There were 2 complete and 9 partial responses, for an overall response rate of 24%. Median duration of response was 5 months. Fourteen women (31%) had stable disease with median duration of response of 5 months. Median survival for the entire group was 12 months. Toxicity was primarily hematologic, and only 3 patients discontinued therapy because of toxicity. QOL surveys indicated that this was a well-tolerated regimen.

CONCLUSION

The combination of gemcitabine and doxorubicin can be safely administered. Overall, approximately 55% of women with platinum-resistant ovarian or peritoneal cancer benefit from this regimen with response or stabilization of disease.

Phase I study of gemcitabine (difluorodeoxycytidine) in children with relapsed or refractory leukemia (CCG-0955): a report from the Children's Cancer Group

To determine the maximum tolerated dose (MTD) and assess the toxicity profile and pharmacokinetics of weekly gemcitabine infusions in pediatric patients with refractory hematologic malignancies. Fourteen patients under 21 years old were given infusions of gemcitabine for escalating durations at 10 mg/m2/min weekly for three consecutive weeks. Two males and two females were studied at each dose level. Pharmacokinetics of the drug's metabolism were measured by high pressure-liquid chromatography (HPLC) for 24 h after the first dose. Intracellular difluorodeoxycytidine triphosphate formation in leukemic blasts was measured in selected patients. The MTD of gemcitabine in these patients was 3600 mg/m2/week for three consecutive weeks (10 mg/m2/min for 360 min). Hepatotoxicity was the dose limiting toxicity. Thirty to fifty percent of patients exhibited fever, rash, or myalgia. Rare instances of hypotension and pulmonary toxicity were observed. Two of six patients [one acute lymphoblastic leukemia (ALL) and one acute myelogenous leukemia (AML)] treated at the MTD had at least M2 marrows, although peripheral blood counts did not recover sufficiently for the patients to be considered in complete response. Pharmacokinetics of gemcitabine fit a two-compartment open model with terminal half-life and plasma clearance value of 62 min and 2.2 l/min/m2, respectively. No gender differences were observed. In conclusion, the MTD of gemcitabine was 10 mg/m2/min for 360 min every week for 3 weeks. This is the recommended phase II dose schedule for children with leukemia. The activity of the drug at this schedule in heavily pretreated, refractory patients warrants a phase II trial in hematologic malignancies.

Toxicity of a 24-hour infusion of gemcitabine in biliary tract and pancreatic cancer: a pilot study

The antitumor activity of gemcitabine is not dose-response related but schedule-dependent. Based on the results of a published phase I study in patients with nonsmall-cell lung cancer we started a pilot study of a 24-hr infusion of gemcitabine in patients with adenocarcinoma of the pancreas and biliary tract cancer. Twenty-five patients were enrolled and received a 24-hr infusion of gemcitabine once weekly on three consecutive out of 4 weeks. Dose levels of gemcitabine ranged from 100 to 150 mg/m2. One of 13 chemotherapy-naive patients had a partial response. Dose-limiting toxicity (DLT) was thrombocytopenia in pretreated patients and neutropenia in chemotherapy-naive patients. Other toxicities were oral mucositis, fever, flu-like symptoms, and asthenia. Maximum tolerated dose (MTD), especially in pretreated patients, was 100 mg/m2.

Radiation therapy and concurrent fixed dose amifostine with escalating doses of twice-weekly gemcitabine in advanced pancreatic cancer

PURPOSE

To determine the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) of twice-weekly gemcitabine (TW-G) when administered in conjunction with fixed dose amifostine (A) during external radiotherapy (RT) in patients with advanced pancreatic cancer.

METHODS AND MATERIALS

Ten patients with previously untreated, locally advanced, or asymptomatic-metastatic pancreatic adenocarcinoma were enrolled in this study. RT was delivered by using the standard four-field technique (1.8 Gy daily fractions, 45 Gy followed by a boost of 5.4 Gy, in 5-1/2 weeks). The starting dose of TW-G was 60 mg/m(2) (i.v., 30-min infusion), which is equal to the upper limit of previously reported MTD of TW-G when given without A during RT. A was given just before the TW-G, at a fixed dose of 340 mg/m(2) (i.v., rapid infusion). TW-G doses were escalated by 30-mg/m(2) increments in successive cohorts of 3 to 6 additional patients until DLT was observed. Toxicities were graded using the Radiation Therapy Oncology Group and National Cancer Institute Common Toxicity Criteria, version 2.0.

RESULTS

In general, therapy was well tolerated in patients treated at the first two dose levels of 60 mg/m(2) and 90 mg/m(2). The DLT of TW-G given in conjunction with A during RT were neutropenia, thrombocytopenia, and nausea/vomiting at the dose level of 120 mg/m(2). Of the 10 patients eligible for a median follow-up of 10 months, 5 remain alive; 1 complete responder, 3 partial responders, and 1 with stable disease.

CONCLUSION

A dose of TW-G at a level of 90 mg/m(2) produced tolerable toxicity and it may possess significant activity when delivered in conjunction with 340 mg/m(2) dose of A during RT of the upper abdomen. Due to the higher MTD of TW-G seen in our study, we consider that the A supplementation may optimize the therapeutic index of TW-G-based chemoradiotherapy protocols in patients with pancreatic carcinoma.

Gemcitabine in hematologic malignancies

Gemcitabine is a pyrimidine analogue that showed significant activity in solid malignancies. Gemcitabine acts by inhibiting DNA synthesis through chain termination and ribonucleotide reductase inhibition. During initial phase I and II studies, gemcitabine had a low toxicity profile and was well tolerated as a single agent and in combination therapy. Recently, there has been more interest in studying the activity of gemcitabine in hematologic malignancies. Gemcitabine demonstrated good activity in refractory Hodgkin disease patients, non-Hodgkin lymphoma, cutaneous T-cell lymphoma, and acute leukemias. There is a preponderance of evidence on the activity of gemcitabine in vitro in myeloma and leukemic cell lines. The activity of gemcitabine in these disorders will pave the way for incorporating this agent into the early phases of therapy.

Second-Line Gemcitabine in Refractory Stage IV Non–Small-Cell Lung Cancer: A Phase II Trial

Two recent trials have suggested that docetaxel improves survival in the second-line treatment of non small-cell lung cancer (NSCLC) refractory to first-line platinum-based regimens. Given this, it is appropriate to continue to address the role of new agents in the second-line treatment of refractory NSCLC. Gemcitabine is a well-tolerated new agent that has been shown to have activity in NSCLC. Thirty-one previously treated patients with NSCLC were entered in this study. Eight patients had responsive disease (defined as response to first-line therapy lasting greater than or equal to 3 months) and 23 had refractory disease (defined as progressive disease on first-line therapy or progression less than 3 months from completing first-line therapy). Gemcitabine (1250 mg/m2) was infused over 30 minutes on days 1, 8, and 15 every 28 days. Quality of life (QOL) was assessed with each cycle using the Functional Assessment Cancer Therapy-Lung (FACT-L) questionnaire. Two patients (6.5%) had a partial response, and nine (29%) had disease stabilization. The most frequent grade 3/4 toxicity was myelosuppression, but this only occurred in 8% of doses delivered. Fifty-two percent of evaluable patients had stable or improved QOL over baseline, 10% had a decline in QOL, and the remainder completed only baseline questionnaires. Twenty-nine patients have died of progressive NSCLC; two patients remain alive. Overall, the 31 patients have a median survival of 5.1 months (95% confidence interval [CI]: 4.2-7.4 months) and 1-year survival rate of 16% (95% CI: 3%-29%). Gemcitabine was well tolerated in this patient population. An objective response rate of 6.5% was observed although a significant proportion of patients (29%) experienced stable disease, which may have impacted on their survival. QOL was improved or maintained in over half of the patients. Given these data, gemcitabine as a single agent is a therapeutic option for patients with refractory NSCLC.

A randomized study comparing two different schedules of administration of cisplatin in combination with gemcitabine in advanced nonsmall cell lung carcinoma

BACKGROUND

This randomized trial was designed to investigate the feasibility, toxicity, and activity of two different schedules of gemcitabine plus cisplatin in previously untreated patients with advanced (International Union Against Cancer (UICC) Stage IIIB-IV) nonsmall cell lung carcinoma (NSCLC).

METHODS

From February 1997 to September 1998, 82 patients with advanced NSCLC were entered onto the study and were randomized to gemcitabine 1000 mg/m(2) on Days 1, 8, and 15 plus cisplatin 80 mg/m(2) on Day 2 (arm A) or Day 15 (arm B) every 28 days.

RESULTS

All the patients were assessable for toxicity (arm A/arm B: 151/177 cycles; median, 4 of 5 cycles per patient), and the following Grade 3-4 toxicities were reported (percentage of cycles in arm A vs. arm B): anemia, 7.9% and 2.3% (P < 0.05); leukopenia, 6.0% and 6.7%; thrombocytopenia, 15.0% and 1.6% (P < 0.01); no World Health Organization (WHO) Grade 3-4 nonhematologic toxicities were observed. These side effects led to gemcitabine dose reductions in 35.1% of courses in arm A and 22.0% of courses in arm B (P < 0.05) and to gemcitabine omissions in 28.5% of courses in arm A versus 7.3% of courses in arm B (P < 0.01). Dose intensities (DIs) of gemcitabine were 607.5 mg/m(2)/week in arm A and 711.6 mg/m(2)/week in arm B (P < 0.01); DIs of cisplatin were 18. 1 mg/m(2)/week in arm A and 18.8 mg/m(2)/week in arm B. The total delivered doses of gemcitabine were 9315.5 mg/m(2) in arm A and 12, 631.0 mg/m(2) in arm B (P < 0.01); the total delivered doses of cisplatin were 277.1 mg/m(2) in arm A and 333.0 mg/m(2) in arm B (P < 0.01). Response rates according to intention to treat were 40.4% (95% confidence interval [CI], 25.5-55.3) in arm A and 45% (95% CI, 29.5-60.5) in arm B. The overall median duration of response was 7.4 months; the median time to disease progression was 6 months (95% CI, 3-9) in arm A and 9 months (95% CI, 4-14) in arm B (P < 0.02); the median overall survival was 10 months (95% CI, 7.0-12.5) in arm A and 17 months (95% CI, 13.0-21.6) in arm B (P < 0.01); the 1-year survival rates were 34% and 63%, respectively.

CONCLUSIONS

Our data show that arm B (cisplatin on Day 15) is less toxic than arm A (cisplatin on Day 2) and allows the administration of significantly higher total doses and dose intensities of chemotherapy. No significant differences in response rates were observed between the two schedules; patients on arm B experienced a significantly more prolonged progression free and overall survival; however, the study was not powered to detect differences in these outcomes.

A novel action of human apurinic/apyrimidinic endonuclease: excision of L-configuration deoxyribonucleoside analogs from the 3' termini of DNA

beta-l-Dioxolane-cytidine (l-OddC, BCH-4556, Troxacitabine) is a novel unnatural stereochemical nucleoside analog that is under phase II clinical study for cancer treatment. This nucleoside analog could be phosphorylated and subsequently incorporated into the 3' terminus of DNA. The cytotoxicity of l-OddC was correlated with the amount of l-OddCMP in DNA, which depends on the incorporation by DNA polymerases and the removal by exonucleases. Here we reported the purification and identification of the major enzyme that could preferentially remove l-OddCMP compared with dCMP from the 3' termini of DNA in human cells. Surprisingly, this enzyme was found to be apurinic/apyrimidinic endonuclease (APE1) (), a well characterized DNA base excision repair protein. APE1 preferred to remove l- over d-configuration nucleosides from 3' termini of DNA. The efficiency of removal of these deoxycytidine analogs were as follows: l-OddC > beta-l-2',3'-dideoxy-2', 3'-didehydro-5-fluorocytidine > beta-l-2',3'-dideoxycytidine > beta-l-2',3'-dideoxy-3'-thiocytidine > beta-d-2',3'-dideoxycytidine > beta-d-2',2'-difluorodeoxycytidine > beta-d-2'-deoxycytidine >/= beta-d-arabinofuranosylcytosine. This report is the first demonstration that an exonuclease can preferentially excise l-configuration nucleoside analogs. This discovery suggests that APE1 could be critical for the activity of l-OddC or other l-nucleoside analogs and may play additional important roles in cells that were not previously known.

Effect of nucleoside analogues and oligonucleotides on hydrolysis of liposomal phospholipids

The hydrolysis of the bilayer forming phospholipids resulting first of all in lysophospholipids and fatty acids is one limiting factor determining the shelf-life of liposomes. In several studies the influence of pH, buffer, lipid composition and other parameters on the hydrolysis of phospholipids have been demonstrated, but the influence of drugs has not yet been investigated systematically. In this study the influence of nucleoside analogues, especially 2', 2'-difluoro 2'-deoxycytidine (gemcitabine, dFdC) on the degradation of phospholipids was elucidated in more detail. It could be demonstrated that the interaction of dFdC with phospholipid bilayers promotes the hydrolysis of phospholipids in a concentration-dependent manner. Obviously two parts of the molecule, the amino group bound to the pyrimidine moiety and the 2', 2'-difluoro-2'-deoxyribose, seem to be responsible for the forced phospholipid hydrolysis. The dFdC-induced hydrolysis of phospholipids was influenced by pH, buffer, lipid composition and different anions. Optimization of the above parameters resulted in prolonged shelf-life of dFdC liposome dispersions, which is an important prerequisite for clinical practice.

Gemcitabine plus vinorelbine as first-line chemotherapy in advanced nonsmall cell lung carcinoma a phase II trial

BACKGROUND

Response and survival in patients with advanced or metastatic nonsmall cell lung carcinoma (NSCLC) remain poor. As single agents, the nucleoside analog gemcitabine, and the semisynthetic vinca alkaloid vinorelbine, have been shown to be effective in NSCLC and to have a low toxicity profile.

METHODS

Fifty-four chemotherapy-naive patients with NSCLC Stage IIIB (any TN3M0 or T4 any NM0) or IV (any T any NM1) were enrolled in this single-institution Phase II study. Gemcitabine 1250 mg/m(2) and vinorelbine 25 mg/m(2) were both administered on Days 1 and 8 every 3 weeks for up to 9 courses unless disease progression or severe toxicity required their discontinuation.

RESULTS

Partial tumor regression was observed in 16 patients, for an overall response rate of 30% (95% confidence interval, 18.4-46.7%) on an intent-to-treat basis. The median time to progression was 5 months (range, 3-20). The median survival was 12 months (range, 5-42+); 1-year and 2-year survival rates were 49.1% and 17%, respectively. Hematologic toxicity was mild with only 11% of the patients developing Grade 3 neutropenia. None of the patients developed any Grade 4 toxicity.

CONCLUSIONS

The combination of gemcitabine plus vinorelbine is feasible on an outpatient basis. The good activity and tolerability of the regimen make it a suitable candidate for further trials, using platinum-based regimens as comparators and possibly selecting elderly and less fit patients.

Gemcitabine and cisplatin as induction regimen for patients with biopsy-proven stage IIIA N2 non-small-cell lung cancer: a phase II study of the European Organization for Research and Treatment of Cancer Lung Cancer Cooperative Group (EORTC 08955)

PURPOSE

Our objective was to better define the activity/feasibility of gemcitabine/cisplatin (GC) as induction chemotherapy in patients with stage IIIA N2 non-small-cell lung cancer (NSCLC) followed by surgery or radiotherapy within a large, ongoing comparative study (EORTC 08941).

PATIENTS AND METHODS

Forty-seven chemotherapy-naive patients with NSCLC, median age of 58 years, stage IIIA N2 disease, World Health Organization performance status of 0 or 1, and the ability to tolerate a pneumonectomy received gemcitabine 1,000 mg/m(2) on days 1, 8, and 15 and cisplatin 100 mg/m(2) on day 2, every 4 weeks. Patients received induction chemotherapy (three cycles) before re-evaluation and randomization to surgery or radiotherapy.

RESULTS

Grade 3/4 thrombocytopenia, the main hematologic toxicity, occurred in 60% of patients but was not associated with bleeding. Full-dose gemcitabine was given in 48% of the courses. Severe nonhematologic toxicity was uncommon. Two patients with preexisting, autoimmune pulmonary fibrosis had deterioration of pulmonary function after radiotherapy. Thirty-three (70.2%; 95% confidence interval, 55.1% to 82.7%) of the 47 eligible patients had objective responses (three complete responses and 30 partial responses). Mediastinal nodes were tumor-free after induction therapy in 53% of cases. Resections were considered complete in 71% of the patients who underwent thoracotomy after induction therapy. Median survival for all recruited patients (N = 53) was 18.9 months, with an estimated 1-year survival rate of 69%.

CONCLUSION

In patients with N2 stage IIIA NSCLC, GC is a highly active and well-tolerated induction regimen. GC should be explored in combination with surgery or radiotherapy in stage I and II patients.

A phase II trial testing gemcitabine as second-line chemotherapy for non small cell lung cancer. The European Lung Cancer Working Party. 101473.1044@compuserve.com

The purpose of the present trial was to determine the activity of gemcitabine as a second-line chemotherapy for non small cell lung cancer (NSCLC). To be eligible, patients had to have pathologically proven NSCLC that has failed to respond to a first-line chemotherapy with a cisplatin-containing regimen, a Karnofsky performance status greater than 50 and adequate renal, haematological and hepatic functions. After registration, patients were treated by gemcitabine given i.v. at a dose of 1 g/m(2) on days 1, 8, 15 every 4 weeks. Response was assessed after two courses of therapy. Eighty-two patients have been registered, five are ineligible and 65 are assessable for response. Four partial responses were observed (6%). No change was documented in 18 cases (28%). Tolerance was good. A few grade III leucopenia and grade III-IV thrombopenia were observed. We conclude that gemcitabine has a modest activity as second-line chemotherapy for NSCLC. It has the advantage to be well tolerated and may thus be one drug to be proposed to the patients who have disease progression after a first-line chemotherapy and who ask for further treatment.

A dose-finding study of gemcitabine and vinorelbine in advanced previously treated malignancies

PURPOSE

Gemcitabine and vinorelbine are active drugs with broad spectrum of activity and manageable toxicity in clinical trials. The aims of this study were to describe the toxicity, to determine the dose-limiting toxicity, and to define the doses of gemcitabine and vinorelbine to be recommended for phase II studies in patients with advanced cancers.

PATIENTS AND METHODS

Drugs were given as 30-min infusions on day 1 and 8 (vinorelbine before gemcitabine) every 3 weeks. Thirty-six patients (male:female ratio 25:11; mean age 54, PS > 60) were treated including 1 retroperitoneal sarcoma, 7 head and neck, 10 lung, 4 thyroid, 6 pancreatic, 1 bladder, 2 ovary, 2 gastric, 1 rectum, 1 unknown primary, and 1 renal cell carcinoma. Doses of gemcitabine/vinorelbine ranged from 800/20 mg/m2 to 1500/30 mg/m2.

RESULTS

The dose-limiting toxicity was neutropenia. A transient grade 2-3 elevation of transaminases was frequently observed at several dose-levels, although this toxicity did not appear to be dose dependant and was reversible at day 21 before the next cycle. Other toxicities were mild and easily manageable, consisting of fatigue and flu-like syndromes. Since the MTD was not reach at the higher dose-level, the recommended dose level of the gemcitabine-vinorelbine combination was 1500/30 mg/m2. One toxic death due to hematologic toxicity was reported in a heavily pretreated patient who underwent prior chemotherapy and pelvic radiotherapy. A total of 12 patients were treated at the recommended dose level which was associated with grade 3-4 neutropenia in 3 of 12 patients and in 22.9% of cycles.

CONCLUSIONS

This study estimates that the recommended dose for phase II studies of gemcitabine-vinorelbine is 1500/30 mg/m2 at day 1 and 8 every three weeks. A careful monitoring of the hematologic toxicity is recommended in heavily pretreated patients and in patients who received pelvic radiotherapy. Partial responses observed in a patient with an advanced cisplatin-5-fluorouracil-resistant pancreatic adenocarcinoma and in a patient with mesothelioma support further evaluation of this combination in patients with tumors refractory to classical antitumor agents.

The role of single-agent gemcitabine in the treatment of non-small-cell lung cancer

Gemcitabine is a novel antimetabolite which has shown anti-tumor activity against a variety of tumors including non-small-cell lung cancer (NSCLC). Phase I clinical trials with gemcitabine revealed it was well tolerated and several phase II trials were conducted. This report will summarize the data from 15 phase I-II trials conducted in both untreated and treated patients with advanced lung cancer. Overall, single-agent gemcitabine was active with response rates in untreated patients ranging from 14%-33% and 0%-25% in previously treated patients. Grade 4 toxicities were infrequent with neutropenia reported in 2%-6% of patients and grade 4 thrombocytopenia was rate (1%). One randomized phase III trial comparing the efficacy and safety of gemcitabine to best supportive care confirmed the role of gemcitabine as an active agent for the treatment of NSCLC. Furthermore, gemcitabine was shown in several economic models to be cost-effective. In summary single agent gemcitabine is active, minimally toxic, and cost-effective as a treatment regimen for patients with advanced lung cancer. Studies combining gemcitabine with other active agents are underway and have reported promising results. As monotherapy, gemcitabine may make a valuable contribution to those patients with a poor performance status or comorbid diseases desiring treatment studies in this setting should also be considered.