Treatment of advanced pancreatic adenocarcinoma with 5-FU, leucovorin, interferon-alpha-2b, and cisplatin

Potentials of interferon therapy in the treatment of pancreatic cancer

Pancreatic cancer is a highly aggressive malignancy with limited treatment options. To improve survival for patients with pancreatic cancer, research has focused on other treatment modalities like adding biological modulators such as type-I interferons (IFNs). Type I IFNs (ie, IFN-α/IFN-β) have antiproliferative, antiviral, and immunoregulatory activities. Furthermore, they are able to induce apoptosis, exert cell cycle blocking, and sensitize tumor cells for chemo- and radiotherapy. A few years ago in vitro, in vivo, and several clinical trials have been described regarding adjuvant IFN-α therapy in the treatment of pancreatic cancer. Some studies reported a remarkable increase in the 2- and 5-year survival. Unfortunately, the only randomized clinical trial did not show a significant increase in overall survival, although the increased median survival implicated that some patients in the experimental group benefited from the adjuvant IFN-α therapy. Furthermore, encouraging in vitro and in vivo data points to a possible role for adjuvant IFN therapy. However, up till now, the use of IFNs in the treatment of pancreatic cancer remains controversial. This review, therefore, aims to describe, based on the available data, whether there is a distinct role for IFN therapy in the treatment of pancreatic cancer.

Type I interferons in the treatment of pancreatic cancer: mechanisms of action and role of related receptors

OBJECTIVE

We evaluated the role of type I interferons (IFNs) and IFN receptors in the regulation of cell growth in 3 human pancreatic adenocarcinoma cell lines (BxPC-3, MiaPaCa-2, and Panc-1).

BACKGROUND

Chemotherapy and radiotherapy have a marginal role in the management of pancreatic adenocarcinoma. The addition of IFN-alpha showed promising results in early clinical trials.

METHODS

Cell proliferation and apoptosis were evaluated by DNA measurement and DNA fragmentation, respectively. Type I IFN receptor (IFNAR-1 and IFNAR-2 subunits) was determined by quantitative RT-PCR and immunocytochemistry. Cell cycle distribution was evaluated by propidium iodide staining and flow-cytometric analysis.

RESULTS

The incubation with IFN-beta for 6 days showed a potent inhibitory effect on the proliferation of BxPC-3 (IC(50), 14 IU/mL) and MiaPaCa-2 (IC(50), 64 IU/mL). The inhibitory effect of IFN-beta was stronger than IFN-alpha in all 3 cell lines and mainly modulated by the stimulation of apoptosis, although cell cycle arrest was induced as well. The expression of the type I IFN receptors was significantly higher in BxPC-3 (the most sensitive cell line to IFN) and mainly localized on the membrane, whereas in Panc-1 (the most resistant cell line) about 60% to 70% of cells were negative for IFNAR-2c with a mainly cytoplasmic staining for IFNAR-2c.

CONCLUSION

The antitumor activity of IFN-beta is more potent than IFN-alpha in pancreatic cancer cell lines through the induction of apoptosis. Further studies should investigate in vivo whether the intensity and distribution of IFNAR-1 and IFNAR-2c may predict the response to therapy with IFN-alpha and IFN-beta in pancreatic cancer.

Potential of interferon-alpha in solid tumours: part 2

The second part of this review examines the use of recombinant interferon-alpha (rIFNalpha) in the following solid tumours: superficial bladder cancer, Kaposi's sarcoma, head and neck cancer, gastrointestinal cancers, lung cancer, mesothelioma and ovarian, breast and cervical malignancies. In superficial bladder cancer, intravesical rIFNalpha has a promising role as second-line therapy in patients resistant or intolerant to intravesical bacille Calmette-Guérin (BCG). In HIV-associated Kaposi's sarcoma, rIFNalpha is active as monotherapy and in combination with antiretroviral agents, especially in patients with CD4 counts >200/mm(3), no prior opportunistic infections and nonvisceral disease. rIFNalpha has shown encouraging results when used in combination with retinoids in the chemoprevention of head and neck squamous cell cancers. It is effective in the chemoprevention of hepatocellular cancer in hepatitis C-seropositive patients. In neuroendocrine tumours, including carcinoid tumour, low-dosage (</=3 MU) or intermediate-dosage (5 to 10 MU) rIFNalpha is indicated as second-line treatment, either with octreotide or alone in patients resistant to somatostatin analogues. Intracavitary IFNalpha may be useful in malignant pleural effusions from mesothelioma. Similarly, intraperitoneal IFNalpha may have a role in the treatment of minimal residual disease in ovarian cancer. In breast cancer, the only possible role for IFNalpha appears to be intralesional administration for resistant disease. IFNalpha may have a role as a radiosensitising agent for the treatment of cervical cancer; however, this requires confirmation in randomised trials. On the basis of current evidence, the routine use of rIFNalpha is not recommended in the therapy of head and neck squamous cell cancers, upper gastrointestinal tract, colorectal and lung cancers, or mesothelioma. Pegylated IFNalpha (peginterferon-alpha) is an exciting development that offers theoretical advantages of increased efficacy, reduced toxicity and improved compliance. Further data from randomised studies in solid tumours are needed where rIFNalpha has activity, such as neuroendocrine tumours, minimal residual disease in ovarian cancer, and cervical cancer. A better understanding of the biological mechanisms that determine response to rIFNalpha is needed. Studies of IFNalpha-stimulated gene expression, which are now feasible, should help to identify molecular predictors of response and allow us to target therapy more selectively to patients with solid tumours responsive to IFNalpha.

Gene therapy for intraperitoneally disseminated pancreatic cancers by Escherichia coli uracil phosphoribosiltransferase (UPRT) gene mediated by restricted replication-competent adenoviral vectors

Although patients with unresectable pancreatic tumors have been treated with 5-fluorouracil (5FU)-based combination chemotherapy, the drug resistance of cancer cells presents a crucial therapeutic problem. It was reported that UPRT overcomes 5FU resistance. UPRT catalyzes the synthesis of 5-fluorouridine monophosphate (FUMP) from Uracil and phosphoribosylpyrophosphate (PRPP). The antitumor effect of 5FU is enhanced by augmenting 5-fluorodeoxyuridine monophosphate (FdUMP) converted from FUMP, which inhibits thymidylate synthetase (TS). We first demonstrated that injecting an E1-deficient adenoviral vector (Adv) expressing UPRT (AxCAUPRT) followed by 5-FU treatment resulted in a volume reduction of xenotransplanted human tumors. In examining the therapeutic effect of AxCAUPRT/5-FU against peritoneal dissemination, we found that non-selective gene transduction of AxCAUPRT caused severe adverse effects arising from the increase of F-dUMP in normal intestine. Because the therapeutic gene delivered by a restricted replication-competent Adv lacking 55 kDa E1B protein (AxE1AdB) is speculated to be expressed selectively in tumors, mice with established tumors were injected with AxE1AdB and E1-deleted Adv expressing the lacZ reporter gene (AxCAlacZ). The expression of the reporter gene (lacZ) was selectively enhanced in disseminated tumors. The therapeutic advantage of restricted replication competent Adv that expresses UPRT (AxE1AdB-UPRT) was evaluated in an intraperitoneal disseminated tumor model. To study the anti-tumor effect of AxE1AdB-UPRT/5FU, mice with disseminated AsPC-1 tumors were administered the Adv, followed by the 5FU treatment. It was shown that the treatment with AxE1AdB-UPRT/5FU caused a dramatic reduction of the disseminated tumor burden without toxicity in normal tissues. Our results showed that the AxE1AdB-UPRT/5FU system is a promising tool for intraperitoneal disseminated pancreatic cancer.

Gene therapy for pancreatic cancer

Gene transfer technology has the potential to revolutionize cancer treatment. Developments in molecular biology, genetics, genomics, stem cell technology, virology, bioengineering, and immunology are accelerating the pace of innovation and movement from the laboratory bench to the clinical arena. Pancreatic adenocarcinoma, with its particularly poor prognosis and lack of effective traditional therapy for most patients, is an area where gene transfer and immunotherapy have a maximal opportunity to demonstrate efficacy. In this review, we have discussed current preclinical and clinical investigation of gene transfer technology for pancreatic cancer. We have emphasized that the many strategies under investigation for cancer gene therapy can be classified into two major categories. The first category of therapies rely on the transduction of cells other than tumor cells, or the limited transduction of tumor tissue. These therapies, which do not require efficient gene transfer, generally lead to systemic biological effects (e.g., systemic antitumor immunity, inhibition of tumor angiogenesis, etc) and therefore the effects of limited gene transfer are biologically "amplified." The second category of gene transfer strategies requires the delivery of therapeutic genetic material to all or most tumor cells. While these elegant approaches are based on state-of-the-art advances in our understanding of the molecular biology of cancer, they suffer from the current inadequacies of gene transfer technology. At least in the short term, it is very likely that success in pancreatic cancer gene therapy will involve therapies that require only the limited transduction of cells. The time-worn surgical maxim, "Do what's easy first," certainly applies here.

The role of gemcitabine alone and in combination in the treatment of pancreatic cancer

Pancreatic cancer, one of the most frequently reported gastrointestinal tumors, has a 5-year survival of less than 5%. Despite representing only 2-3% of the total cancer incidence, it is the fifth leading cause of cancer death. This is because it is commonly only diagnosed at an advanced stage. Until recently the traditional therapy for patients with advanced disease was palliative 5-fluorouracil (5-FU)-based chemotherapy. However, the novel antinucleoside gemcitabine (Gemzar) has demonstrated a survival benefit over 5-FU, and an improvement in disease-related symptoms and quality of life in patients with advanced disease. This review presents an overview of the clinical studies of gemcitabine, either alone or in combination, with other chemotherapeutic agents and/or radiation therapy, in the treatment of these patients. A comparison of these studies is made with those using alternative treatment regimens. The data suggest that gemcitabine in combination with biomodulated 5-FU should be considered the standard palliative treatment to which other new drug combinations or combined modality chemoradiation regimens should be compared.

Current status of and future prospects for the medical management of adenocarcinoma of the exocrine pancreas

Adenocarcinoma of the exocrine pancreas is one of the most refractory neoplasms to medical treatment. Although of marginal value, 5-fluorouracil (5-FU) alone or in combination with other agents or modalities has been the standard surgical adjuvant approach to localized unresectable tumor as well as the standard treatment for disseminated pancreatic cancer. Recently, a new chemotherapeutic agent, gemcitabine, has been shown to be somewhat more effective than 5-FU against metastatic pancreatic cancer. Treatment with gemcitabine usually results in a greater likelihood of objective response and better symptom control than treatment with 5-FU or drug combinations that include 5-FU. However, treatment with gemcitabine does not improve overall survival of patients with disseminated neoplasm. Newer promising agents such as 9-nitrocamptothecin have recently entered clinical trials, and novel modalities (e.g., gene therapy) are nearing full-scale clinical trial. There are reasons to believe that these and other new initiatives may soon significantly improve the medical management of adenocarcinoma of the exocrine pancreas.

A phase II study: docetaxel as first-line chemotherapy for advanced pancreatic adenocarcinoma

The aim of this study was to evaluate the efficacy of docetaxel as first-line chemotherapy in patients with unresectable metastatic or locally advanced pancreatic adenocarcinoma and to further characterise the safety and pharmacokinetic profiles of docetaxel. 43 patients were enrolled into this phase II study. Treatment consisted of a 1-h infusion of docetaxel 100 mg/m2 every 3 weeks without premedication with corticosteroids until progression or unacceptable toxicity occurred. Dose modifications were planned for adverse events. Patients were observed for 1 month after the last docetaxel infusion, to document any late adverse events, with a follow-up every 3 months until death. Response rate and duration were the major efficacy endpoints. Response status was reviewed by an external independent panel. Pharmacokinetic analysis was performed during the first treatment cycle. 40 patients were evaluable for response, and all were evaluable for safety. After independent review, partial response was recorded in 6 patients (overall response rate, 15%; 95% confidence limit (CI), 7.7-29.8%) and stable disease was recorded in 15 patients (38%). The median duration of response was 5.1 months (range: 3.1-7.2). The median pain control time was 4.5 months (range: 0-8) and the median time to performance status worsening was 2.3 months (range: 0-4.5). Most patients 40 (93.0%) received a relative dose intensity of more than 70% of the planned dose. The incidence and severity of adverse events reflected the known safety profile for docetaxel. Docetaxel clearance was reduced in patients with elevated concentrations of hepatic enzymes or bilirubin. Docetaxel is an active agent for unresectable metastatic or locally advanced pancreatic adenocarcinoma.

La Chemioterapia Adiuvante Concomitante Del Carcinoma Pancreatico

Pancreatic cancer is a leading cause of cancer death. Despite improvement in diagnosis and treatment in the last 15 years, mortality rates essentially equal the incidence of the disease. Combination treatment with chemoradiation yields up to now better results than chemotherapy or radiotherapy given alone in consideration of substantial radio and chemoresistance of the cancer cells. This study will review the most important literature data about combination adjuvant treatment and preoperative (primary) chemoradiation in pancreatic cancer. Some other reports will be given on locoregional chemotherapy and finally a brief view on a possible perspective for promising future treatments coming from data of molecular pathology.

Adjuvant chemoradiation after surgery has been shown to be superior to operation alone in potentially resectable pancreatic cancer in many studies, in terms both of local control and median overall survival. Unfortunately, a consistent percentage of patients cannot receive adjuvant treatment since late recovery after surgery or postoperative morbidity. Owing to this last reason, many authors prefer primary chemoradiation in potentially resectable pancreatic cancer; neoadjuvant treatment find out its background in other relevant biological and clinical evaluations.

Some studies report encouraging results with primary chemoradiation using 5-fluorouracil. Other experiences with relatively new drugs, with potent radiosensiting effect, such as gemcitabine or taxol are going on; many of these are phase I studies. Clinical research in the field of preoperative treatment is up to now emerging in some importants Oncological Institutions. The principal actual aim seems to be that of forsee periods of treatment which will be brief and use the dose of chemotherapy that is active, giving acceptable toxicity.

Ongoing trials will give, in the next years, the answer about the improvement of efficacy of treatments largely expected by all researchers.