Review article: current treatment and optimal patient management in pancreatic cancer

Fabrication of gold nanoparticles for targeted therapy in pancreatic cancer

The targeted delivery of a drug should result in enhanced therapeutic efficacy with low to minimal side effects. This is a widely accepted concept, but limited in application due to lack of available technologies and process of validation. Biomedical nanotechnology can play an important role in this respect. Biomedical nanotechnology is a burgeoning field with myriads of opportunities and possibilities for advancing medical science and disease treatment. Cancer nanotechnology (1-100 nm size range) is expected to change the very foundations of cancer treatment, diagnosis and detection. Nanomaterials, especially gold nanoparticles (AuNPs) have unique physico-chemical properties, such as ultra small size, large surface area to mass ratio, and high surface reactivity, presence of surface plasmon resonance (SPR) bands, biocompatibility and ease of surface functionalization. In this review, we will discuss how the unique physico-chemical properties of gold nanoparticles may be utilized for targeted drug delivery in pancreatic cancer leading to increased efficacy of traditional chemotherapeutics.

Primary advanced unresectable pancreatic cancer

Median as well as overall survival of pancreatic cancer patients in the advanced stage is extremely low despite advances in cancer therapy regarding tumor cell biology, therapy resistance, and diagnosis. In matters of chemoradiation therapy (CRT) in locally advanced pancreatic cancer, favorable positive effect has been reached with different radiotherapy proceedings such as intraoperative radiation therapy with or without external chemo-/radiation therapy or with CRT alone with regard to local tumor pain, local tumor remission, or local control of disease and overall survival. Primary (chemo-) radiation therapy only rarely leads to local remission. Intraoperative radiation therapy (IORT) merely reaches pain palliation in most cases. By administering up-to-date primary CRT, especially with gemcitabine-associated CRT, local remission in up to 50% of patients can be observed. By applying neoadjuvant CRT, better resectability and the reduction of postoperative positive lymph node metastasis has been seen in patients with resectable or possibly resectable pancreatic cancer. With primary CRT, resectability can also be achieved in patients with primary unresectable pancreatic cancer. It has been shown at the evaluation of patients' progression samples--either treated with neoadjuvant or primarily with radiotherapy (with conventional radiation technique)--that the rate of local recurrence or local progression can be reduced in comparison with historical cohorts. By contrast, the rate on distant metastases was not affected. Whereas concurrent CRT leads to favorable local tumor control, this procedure has a minor effect as to the survival in most of the studies. Because metastases occur mostly out of the irradiation field and because of partly advanced local tumor progression, the concept of combined CRT with continuing chemotherapy was developed. Median survival of pancreatic patients in the advanced stage is approx. 3-5 months, with a 12-month survival probability of 10% despite advances in cancer therapy. On the other hand, the 5-year survival probability is 0.4%-3.0%. The causes of such a dismal prognosis can be understood first of all in the commonly late diagnosis, second in the aggressive tumor cell biology with continuing therapy resistance, and finally because an acceptable resection rate can be achieved only in specialized centers. Only 10%-15% of patients can be resected after the diagnosis of pancreatic cancer. Resection is considered a potential curative therapy. However, median survival of these patients amounts to only 13-18 months, with a 5-year survival of 10%-20%. The survival rate did not improve with a radical resection and extended lymphadenectomy. Furthermore, 15%-30% of primary nonmetastatic pancreatic cancer is unresectable due to extended vessel infiltration at time of diagnosis. The prognosis for these patients is very dismal due to lack of specific therapy; moreover, median overall survival is a maximum of 6-8 months.

The immunocytokine scFv23/TNF targeting HER-2/neu induces synergistic cytotoxic effects with 5-fluorouracil in TNF-resistant pancreatic cancer cell lines

Human pancreatic tumor cells are highly resistant to both tumor necrosis factor (TNF) and to chemotherapeutic agents. HER-2/neu expression has been proposed as a negative prognostic marker in pancreatic intraepithelial neoplasia. Our approach was to utilize HER-2/neu expression on the surface of tumor cells as a therapeutic target employing scFv23/TNF, immunocytokine composed of a single chain Fv antibody (scFv23) targeting the HER-2/neu and the cytokine TNF as the cytotoxic moiety, to deliver TNF directly to TNF-resistant pancreatic tumor cells. Using a panel of human pancreatic cell lines, which overexpress HER-2/neu, we evaluated the in vitro response of cells to TNF, scFv23/TNF, Herceptin, and a combination of scFv23/TNF with various chemotherapeutic agents. We found that all pancreatic cancer cell lines were highly resistant to the cytotoxic effects of TNF and that scFv23/TNF was highly cytotoxic to TNF-resistant HER-2/neu-expressing pancreatic cancer cell lines at levels rivaling that of conventional chemotherapeutic agents. Combination studies demonstrated a synergistic cytotoxic effect of scFv23/TNF with 5-fluorouracil (5-FU) in TNF-resistant pancreatic cancer cell lines. Mechanistic studies demonstrated that the 5-FU plus scFv23/TNF combination specifically resulted in a down-regulation of HER-2/neu, p-Akt and Bcl-2 and up-regulation of TNF-R1. In addition, the combination 5-FU plus scFv23/TNF induced apoptosis and this synergistic effect was dependent on activation of caspase-8 and caspase-3. Delivery of the cytokine TNF to HER-2/neu expressing pancreatic tumor cells, which are inherently resistant to TNF using scFv23/TNF may be an effective therapy for pancreatic cancer especially when utilized in combination with 5-FU.

The effect of jaundice on the generation of anti-gastrin antibodies in G17DT immunized patients with advanced pancreatic cancer

AIM

The aim of this study was to determine the ability of G17DT to generate anti-gastrin antibodies in jaundiced patients with biliary obstruction due to advanced pancreatic cancer.

METHODS

G17DT was administered to 41 patients with advanced pancreatic adenocarcinoma by intramuscular (i.m.) injection at a dose of 250mcg at weeks 0, 1 and 3 of the study.

RESULTS

Thirty-five of 41 patients participating in the study were categorized as responders in terms of their gastrin-17 antibody response. There was no correlation between the maximum G17 antibody response and the bilirubin level at either week 0 or week 12. The median survival of patients from the time of the first injection of G17DT was 204 days with 25% of patients surviving for <or=97 days and 25% of patients surviving for >or=305 days.

CONCLUSION

This study shows that G17DT administered to jaundiced patients with advanced pancreatic cancer is immunogenic and well tolerated.

The outcome of laparoscopic gastrojejunostomy in malignant gastric outlet obstruction

BACKGROUND AND AIMS

The development of gastric outlet obstruction (GOO) in patients with advanced pancreatic cancer is regarded by some as a terminal event. There are several interventional options available, one of which is laparoscopic gastrojejunostomy (LGJ). To date, there are little data on the effectiveness of this intervention. Using patient records we sought to analyze our own experience of LGJ in patients with terminal pancreatic cancer.

METHODS

A retrospective analysis of all patients with pancreatic or peri-ampullary cancer that underwent LGJ for GOO. All LGJ were performed by two consultant surgeons at Glasgow Royal Infirmary. Patient notes were assessed for survival time after LGJ; post-operative complications; resumption of oral intake; time to discharge and recurrence of GOO after surgery.

RESULTS

A total of 18 patients underwent LGJ for GOO between 2000 and 2004. Median age at time of procedure was 66.5 yr (range 40 to 79). Two patients were converted to an open procedure for technical reasons, both of whom died in the post-operative period. Of the remaining 16, 15 had successful relief of GOO. The remaining patient underwent revisional open surgery 15 d post-operatively due to persistent GOO. Two patients died in hospital but 14 were discharged with symptom relief. Median survival for these patients was 59 d (range 12 to 248).

CONCLUSION

The development of GOO in pancreatic and peri-ampullary cancer should not be regarded as a terminal event. LGJ should be considered as a treatment option in these patients.

Expression and localization of human multidrug resistance protein (ABCC) family members in pancreatic carcinoma

Pancreatic ductal adenocarcinoma is among the top 10 causes of death from cancer in industrialized countries. In comparison with other gastrointestinal malignancies, pancreatic cancer is one of the tumors most resistant to chemotherapy. An important mechanism of tumor multidrug resistance is increased drug efflux mediated by several transporters of the ABC superfamily. Especially BCRP (ABCG2), MDR1 P-glycoprotein (ABCB1) and members of the MRP (ABCC) family are important in mediating drug resistance. The MRP family consists of 9 members (MRP1-MRP9) with MRP1-MRP6 being best characterized with respect to protein localization and substrate selectivity. Here, we quantified the mRNA expression of BCRP and of all MRP family members in normal human pancreas and pancreatic carcinoma and analyzed the mRNA level of the transporters most abundantly expressed in pancreatic tissue, BCRP, MRP1, MRP3, MRP4 and MRP5, in 37 tissue samples. In addition, we determined the localization of the 4 MRP proteins in normal human pancreas and in pancreatic carcinoma. The expression of BCRP, MRP1 and MRP4 mRNA did not correlate with tumor stage or grading. On the other hand, the expression of MRP3 mRNA was upregulated in pancreatic carcinoma samples and was correlated with tumor grading. The MRP5 mRNA level was significantly higher in pancreatic carcinoma tissue compared to normal pancreatic tissue. These data suggest that MRP3 and MRP5 are involved in drug resistance of pancreatic tumors and that quantitative analysis of their expression may contribute to predict the benefit of chemotherapy in patients with pancreatic cancer.

A phase II study of raltitrexed and gemcitabine in patients with advanced pancreatic carcinoma

Advanced adenocarcinoma of the pancreas has a very poor prognosis. The aim of this study was to assess the efficacy and tolerability of a combination of the chemotherapeutic agents gemcitabine and raltitrexed. Chemonaïve patients with advanced adenocarcinoma of the pancreas were treated with a combination of raltitrexed (3.5 mg m⁻² on day 1 of a 21-day treatment cycle) and gemcitabine (800 mg m⁻² intravenously (i.v.) on days 1 and 8 of a 21-day cycle). Between April 2000 and February 2003, 27 patients were enrolled onto the study. The mean duration of treatment was 11 weeks. Four of 27 patients experienced at least one episode of grade 3 or 4 neutropenia. One patient with grade 4 neutropenia died due to sepsis. Four of 27 patients experienced grade 4 diarrhoea. There was one partial remission (4%) and 12 patients experienced disease stabilisation (44%). The 6-month and 1-year survival rates were 37 and 11%, respectively. Symptomatic benefit occurred in seven (26%) patients. We conclude that a combination of raltitrexed and gemcitabine, using the schedule and doses in this study, cannot be recommended for patients with advanced pancreatic cancer.

Cancer in the elderly: pancreatic cancer

Pancreatic cancer remains a devastating and difficult disease to diagnose and successfully treat. Its incidence increases with age, with 60% of patients being over the age of 65 at presentation. Due to the insidious nature and asymptomatic onset of pancreatic cancer approximately 85% of patients present with disseminated or locally advanced disease resulting in a very poor prognosis. In the past the elderly patient, who may be felt to be too frail for operative procedures or further therapy, may have missed out on optimal treatment. In this article we review the investigation and treatment of pancreatic cancer and examine current evidence with regard to pancreatic cancer in the elderly. The evidence suggests that surgical resection can be performed safely in patients who are fit for surgery in specialist centres but may require more intensive post-operative rehabilitation.

Pilot study of celecoxib and infusional 5-fluorouracil as second-line treatment for advanced pancreatic carcinoma

BACKGROUND

Cyclooxygenase-2 (COX-2) is up-regulated frequently and may constitute a promising therapeutic target in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

Patients with advanced PDAC who had progressive disease after gemcitabine-based chemotherapy were eligible for this pilot study. Treatment was comprised of oral celecoxib (400 mg twice daily) and protracted intravenous (i.v.) infusion 5-fluorouracil (5-FU) (200 mg/m(2) per day), both given continuously for a maximum of 9 treatment months, in the absence of disease progression or unacceptable toxicity. Patients were examined weekly for toxicity and were restaged every 6-8 weeks for tumor assessment.

RESULTS

Seventeen patients entered the study. Asymptomatic transaminase elevation was the most common toxicity and reached NCI-CTC (version 3.0) Grade 3-4 in 4 of 133 treatment weeks. No other hematologic or nonhematologic toxicity > Grade 2 was observed. Four patients discontinued celecoxib due to upper gastrointestinal tract toxicity. Two confirmed partial responses (durations of 23 weeks and 68 weeks, respectively) and 2 patients with stable disease (durations of 10 weeks and 13 weeks, respectively) were observed for an overall response rate of 12% (95% confidence interval, 0-27%) in the intent-to-treat population. A significant decrease (> or = 50%) in serum CA 19.9 levels was observed in 3 of 9 evaluable patients. The median time to disease progression was 8 weeks, and the median overall survival was 15 weeks.

CONCLUSIONS

The combination of oral celecoxib and 5-FU by protracted i.v. infusion was found to be feasible and well tolerated, and was capable of inducing durable objective responses, even in patients with far advanced, gemcitabine-resistant/refractory PDAC. Further exploration of COX-2 inhibitor/fluropyrimidine combinations is warranted.

Review article: chemotherapy for pancreatic cancer

Pancreatic cancer is a common, highly lethal disease that is rising in incidence. Chemotherapy based on 5-fluorouracil (5-FU) has been shown to prolong survival in advanced pancreatic cancer. Gemcitabine improves major symptoms and survival outcomes compared with bolus 5-FU. Many novel small molecules are being widely and actively researched. These compounds are based on classical mechanisms of action as well as biological therapies targeting novel cellular survival pathways, and include fluoropyrimidines, nucleoside cytidine analogues, platinum analogues, topoisomerase-inhibitors, antimicrotubule agents, proteasome inhibitors, vitamin D analogues, arachidonic acid pathway inhibitors, histone deacytylator inhibitors, farnesyltransferase inhibitors and epidermal growth factor receptor therapies. Adjuvant chemotherapy has also demonstrated the best survival outcomes following resection compared to other adjuvant or neo-adjuvant strategies such as radiation-based treatments. These benefits are superimposed on the dramatic increase in resectability rates and reduction in post-operative mortality achieved by centralisation of treatment in high-volume speciality centres. Newer 'small-molecule' drugs as well as the latest 'large-molecule' biological agents hold considerable promise for the future. Real advances are anticipated over the next five years but are dependent on large randomised controlled trials for success.

Influence of conjugated and conventional linoleic acid on tumor growth and lipid peroxidation in pancreatic adenocarcinoma in hamster

Conventional linoleic acid (LA) is regarded as a promotor of carcinogenesis. However, the effect of its conjugated derivative on cancer is still unknown. Therefore we investigated the influence of conventional and conjugated LA on tumor growth and lipid peroxidation in a solid model of pancreatic adenocarcinoma in Syrian hamsters. 60 male hamsters were randomized in 4 groups (Gr.) (n=15). Gr. 1 and 2 received 0.5 ml 0.9% sodium chloride subcutaneously (s.c.) once a week while Gr. 3 and 4 were injected 10 mg N-nitrosobis-2-oxopropylamine (BOP)/kg body weight weekly for 12 weeks to induce pancreatic cancer. Gr. 1 and 3 received a diet containing conventional LA, Gr. 2 and 4 were fed a diet of conjugated LA. After 29 weeks all animals were sacrificed, pancreas was weighed and examined macroscopically and histologically. The level of lipid peroxidation and activities of glutathion peroxidase and superoxide dismutase were determined in tumor-free as well as in pancreatic carcinoma tissue. Different diets did not influence the incidence of pancreatic carcinoma, however, pancreas weight was increased by conjugated LA compared to conventional LA. Furthermore both diets decreased the activity of glutathion peroxidase and increased the level of lipid peroxidation in pancreatic intratumoral tissue. The content of conjugated LA in dietary did not influence pancreatic tumor growth in a solid model of pancreatic adenocarcinoma in Syrian hamsters.

Adjuvant therapy in pancreatic cancer: historical and current perspectives

The results from pancreatic ductal adenocarcinoma appear to be improving with increased resection rates and reduced postoperative mortality reported by specialist pancreatic cancer teams. Developments with medical oncological treatments have been difficult, however, due to the fundamentally aggressive biological nature of pancreatic cancer and its resistance to chemotherapy coupled with a relative dearth of randomised controlled trials. The European Study Group for Pancreatic Cancer (ESPAC)-1 trial recruited nearly 600 patients and is the largest trial in pancreatic cancer. The results demonstrated that the current best adjuvant treatment is chemotherapy using bolus 5-fluorouracil with folinic acid. The median survival of patients randomly assigned to chemoradiotherapy was 15.5 months and is comparable with many other studies, but the median survival in the chemotherapy arm was 19.7 months and is as good or superior to multimodality treatments including intra-operative radiotherapy, adjuvant chemoradiotherapy and neo-adjuvant therapies. The use of adjuvant 5-fluorouracil with folinic acid may be supplanted by gemcitabine but requires confirmation by ongoing clinical trials, notably ESPAC-3, which plans to recruit 990 patients from Europe, Canada and Australasia. Major trials such as ESPAC-1 and ESPAC-3 have set new standards for the development of adjuvant treatment and it is now clear that such treatment in this field has the potential to significantly improve both patient survival and quality of life after curative resection.

Surgical and medical therapy for pancreatic carcinoma

Progress on the treatment of pancreatic ductal adenocarcinoma has involved advances in medical and surgical care with important contributions from disciplines such as radiology and intensive care. In the last decade large randomized controlled trials have been undertaken that demonstrate the improved patient outcomes. There is an increased risk of pancreatic cancer in chronic pancreatitis, hereditary pancreatitis and a variety of familial cancer syndromes. The optimum outcome from pancreatic cancer needs management by multidisciplinary teams in regional specialist units. Endoscopic stenting, good pain relief and pancreatic enzyme supplementation are the basis of care in advanced pancreatic cancer. Chemotherapy prolongs survival in advanced pancreatic cancer with little to be gained using drugs other than 5FU. Resection, if possible, prolongs life and provides the best quality of life. Adjuvant chemoradiotherapy is of no benefit but chemotherapy may improve survival. Alongside the evolution in clinical management has been the elucidation of the molecular events that underlie pancreatic cancer and this knowledge has guided the introduction of targeted treatments for pancreatic cancer.

Adjuvant therapy in pancreatic cancer

The outlook for patients with pancreatic cancer has been grim. There have been major advances in the surgical treatment of pancreatic cancer, leading to a dramatic reduction in post-operative mortality from the development of high volume specialized centres. This stimulated the study of adjuvant and neoadjuvant treatments in pancreatic cancer including chemoradiotherapy and chemotherapy. Initial protocols have been based on the original but rather small GITSG study first reported in 1985. There have been two large European trials totalling over 600 patients (EORTC and ESPAC-1) that do not support the use of chemoradiation as adjuvant therapy. A second major finding from the ESPAC-1 trial (541 patients randomized) was some but not conclusive evidence for a survival benefit associated with chemotherapy. A third major finding from the ESPAC-1 trial was that the quality of life was not affected by the use of adjuvant treatments compared to surgery alone. The ESPAC-3 trial aims to assess the definitive use of adjuvant chemotherapy in a randomized controlled trial of 990 patients.

Gene therapy for pancreatic cancer--current and prospective strategies

Pancreatic ductal adenocarcinoma is one of the most common causes of cancer death in the developed world. Long-term survival is currently only achieved through surgical resection. Most patients have locally advanced or metastatic disease at the time of diagnosis and are therefore not amenable to resection, whilst chemotherapy and radiotherapy are by and large ineffective. Gene therapy offers an alternative to current adjuvant strategies. With approximately two-thirds of all gene therapy trials worldwide directed at cancer, the gene therapy approaches that are currently being explored for pancreatic cancer are specifically examined. Gene delivery systems, genetic targets, and combined gene delivery with chemotherapy are discussed in the context of pancreatic cancer treatment.