Pancreatic carcinoma in perspective: A continuing challenge

Pancreatic cancer stem cells: A state or an entity?

Pancreatic ductal adenocarcinoma (PDAC), the most common type of pancreatic cancer, has a median overall survival of 6-12 months and a 5-year survival of less than 7%. While PDAC currently represents the 4th most frequent cause of death due to cancer worldwide, it is expected to become the second leading cause of cancer-related death by 2030. These alarming statistics are primarily due to both the inherent chemoresistant and metastatic nature of this tumor, and the existence of a subpopulation of highly plastic "stem"-like cells within the tumor, known as cancer stem cells (CSCs). Since their discovery in PDAC in 2007, we have come to realize that pancreatic CSCs have unique metabolic, autophagic, invasive, and chemoresistance properties that allow them to continuously self-renew and escape chemo-therapeutic elimination. More importantly, the concept of the CSC as a fixed entity within the tumor has also evolved, and current data suggest that CSCs are states rather than defined entities. Consequently, current treatments for the majority of PDAC patients are not effective, and do not significantly impact overall patient survival, as they do not adequately target the plastic CSC sub-population nor the transient/hybrid cells that can replenish the CSC pool. Thus, it is necessary that we improve our understanding of the characteristics and signals that maintain and drive the pancreatic CSC population in order to develop new therapies to target these cells. Herein, we will provide the latest updates and knowledge on the inherent characteristics of pancreatic CSCs and the CSC niche, specifically the cross-talk that exists between CSCs and niche resident cells. Lastly, we will address the question of whether a CSC is a state or an entity and discuss how the answer to this question can impact treatment approaches.

Preclinical and clinical studies of NK012, an SN-38-incorporating polymeric micelles, which is designed based on EPR effect

Polymeric micelles are ideally suited to exploit the EPR effect, and they have been used for the delivery of a range of anticancer drugs in preclinical and clinical studies. NK012 is an SN-38-loaded polymeric micelle constructed in an aqueous milieu by the self-assembly of an amphiphilic block copolymer, PEG-PGlu(SN-38). The antitumor activity was evaluated in several orthotopic tumor models including glioma, renal cancer, stomach cancer, and pancreatic cancer. Two independent phase I clinical trials were conducted in Japan and the USA. In the preclinical studies, it was demonstrated that NK012 exerted significantly more potent antitumor activity with no intestinal toxicity against various orthotopic human tumor xenografts than CPT-11. In clinical trials, predominant toxicity was neutropenia. Non-hematologic toxicity, especially diarrhea, was mostly Grade 1 or 2 during study treatments. Total 8 partial responses were obtained. According to data of preclinical studies, NK012 showing enhanced distribution with prolonged SN-38 release may be ideal for cancer treatment because the antitumor activity of SN-38 is time dependent. Clinical studies showed that NK012 was well tolerated and had antitumor activity including partial responses and several occurrences of prolonged stable disease across a variety of advanced refractory cancers. Phase II studies are ongoing in patients with colorectal cancer in Japan and in patients with triple negative breast cancer and small cell lung cancer in the USA.

Role of reactive oxygen species in brucein D-mediated p38-mitogen-activated protein kinase and nuclear factor-kappaB signalling pathways in human pancreatic adenocarcinoma cells

BACKGROUND

In human pancreatic adenocarcinoma, nuclear factor-kappa-B (NF-kappaB) transcription factor is constitutively activated that contributes to the resistance of the tumour cells to induced apoptosis. In our earlier studies, we have shown that brucein D (BD) mediated apoptosis through activation of the p38-mitogen-activated protein kinase (MAPK) signalling pathway in pancreatic cancer cells. This study investigated the function of reactive oxygen species (ROS) in BD-mediated p38-MAPK and NF-kappaB signalling pathways in PANC-1 cells.

METHODS

Glutathione and dihydroethidium assays were used to measure the antioxidant and superoxide levels, respectively. The protein expression of p22(phox), p67(phox) and p38-MAPK were examined by western blot. The NF-kappaB activity was evaluated by electrophoretic mobility shift assay.

RESULTS

Treatment with BD depleted the intracellular glutathione levels in PANC-1 cells. Brucein D triggered the activation of NADPH oxidase isoforms, p22(phox) and p67(phox) while enhancing the generation of superoxide. Increases in both intracellular ROS and NADPH oxidase activity were inhibited by an antioxidant, N-acetylcysteine (NAC). Brucein D-mediated activation of p38-MAPK was also inhibited by NAC. However, inhibition of NF-kappaB activity in BD-treated cells was independent of ROS. In vivo studies showed that BD treatment effectively reduced the rate of xenograft human pancreatic tumour in nude mice with no significant toxicity.

CONCLUSION

These data suggest that BD is an apoptogenic agent for pancreatic cancer cells through activation of the redox-sensitive p38-MAPK pathway and inhibition of NF-kappaB anti-apoptotic activity in pancreatic cancer cells.

Antitumour activity of NK012, SN-38-incorporating polymeric micelles, in hypovascular orthotopic pancreatic tumour

Human pancreatic cancer is refractory to chemotherapy partly because of blockage to penetration of anticancer agents. This issue must be taken into account particularly for the drug delivery system (DDS). The aim of the present study is to investigate how NK012 (SN-38-incorporating polymeric micelles) categorised as DDS exerts its antitumour effect in an orthotopic pancreatic tumour model compared with gemcitabine and irinotecan hydrochloride (CPT-11), a low-molecular-weight prodrug of a 7-ethyl-10-hydroxy-camptothecin (SN-38). The maximum tolerated doses (MTDs) of NK012 (30 mg/kg/d), CPT-11 (66.7 mg/kg/d) and gemcitabine (16.5mg/kg/d) were administered to mice bearing human pancreatic cancer cell (SUIT-2) xenografts implanted orthotopically. Antitumour effects of these compounds were evaluated. Drug distribution within the tumour was examined by fluorescence microscopy and high performance liquid chromatography (HPLC). NK012 exerted potent antitumour effects compared with CPT-11 and gemcitabine. A high concentration of NK012 and SN-38 released from NK012 had been observed until 192h. On the other hand, SN-38 converted from CPT-11 was detected only 1h postinjection. Fluorescence from NK012 was detected up to 48h, whereas that from CPT-11 almost disappeared by 24h postinjection. NK012 appeared to exert potent antitumour activity against intractable stroma-rich orthotopic pancreatic tumour xenografts due to its sufficient accumulation followed by the effective sustained release of SN-38 from NK012.

Likelihood ratios of clinical, laboratory and image data of pancreatic cancer: Bayesian approach

PURPOSE

The diagnosis of pancreatic cancer (PC) is most frequently established in advanced stages. The aim of this study is to estimate the likelihood ratios (LRs) of diagnostic data with regards to PC that could be used to approach an earlier diagnosis.

METHODS

A case-control study of 300 patients - 150 histological diagnosed cases of PC and 150 age-matched controls hospitalized for study of jaundice, abdominal pain, weight loss and/or chronic pancreatitis - was conducted. Bayesian probabilities in the form of LRs were estimated for PC predictions.

RESULTS

Probability of PC was associated with jaundice [odds ratio (OR) 2.89; confidence interval (CI) 1.71-4.85], glycemic disturbance (OR 5.64; CI 2.36-13.46), tobacco index >20 (OR 2.11; CI 1.08-4.09) and tumour marker CA 19-9 (OR 9.33; CI 1.36-63.95). Computed tomography showed the highest test performance with regards to PC when comparing with other diagnostic tests. LRs for variables relevant to PC were estimated, among the most relevant: jaundice LR + 1.92, CA 19-9 LR + 5.36 and computed tomography LR + 4.15. The prediction model with an endoscopic retrograde cholangiopancreatography at a tertiary referral hospital determined a 67% probability of detecting PC.

CONCLUSIONS

Through a Bayesian approach we can combine clinical, laboratory and imaging data to approximate to an earlier diagnosis of PC.

Erlotinib: the first biologic in the management of pancreatic cancer

BACKGROUND

Pancreatic cancer remains a major therapeutic challenge largely characterized by chemotherapy-refractory disease and poor responses to currently available treatments. Pivotal studies of combination chemotherapeutic agents with gemcitabine showed that responses may exceed single-agent gemcitabine, but with added toxicities. The EGFR is known to be overexpressed in pancreatic cancer and data suggest that the presence of EGFR is associated with a poor prognosis.

OBJECTIVE

To analyze the current data on erlotinib and compare against other agents targeting against the EGFR pathway in pancreatic cancer.

METHODS

PubMed, Ovid, Cochran and the American Society of Clinical Oncology abstract database were searched using the terms 'erlotinib', 'EGFR', 'cetuximab', 'gemcitabine', 'fluorouracil', 'capecitabine' and 'pancreatic cancer' to identify relevant studies. Only studies using erlotinib in pancreatic cancer patients were reviewed and analyzed.

CONCLUSIONS

The combination of gemcitabine and erlotinib is the first combination therapy to demonstrate survival benefits in pancreatic cancer in a Phase III study albeit a modest one. Increased understanding of the EGFR pathway may permit the use of other targeted agents to either augment therapeutic efficacy or circumvent resistance. It is warranted to develop strategies to truly target our therapy with the EGFR agents by identifying those patients who are most likely to derive benefit and achieve meaningful responses.

Enhanced Antitumor Effect of Combined Triptolide and Ionizing Radiation

PURPOSE

The lack of effective treatment for pancreatic cancer results in a very low survival rate. This study explores the enhancement of the therapeutic effect on human pancreatic cancer via the combination of triptolide and ionizing radiation (IR).

EXPERIMENTAL DESIGN

In vitro AsPC-1 human pancreatic cancer cells were treated with triptolide alone, IR alone, or triptolide plus IR. Cell proliferation was analyzed with sulforhodamine B (SRB) method and clonogenic survival; comparison of apoptosis induced by the above treatment was analyzed by annexin V-propidium iodide (PI) staining. Furthermore, the expression of apoptotic pathway intermediates was measured by the assay of caspase activity and Western blot. Mitochondrial transmembrane potential was determined by JC-1 assay. In vivo, AsPC-1 xenografts were treated with 0.25 mg/kg triptolide, 10 Gy IR, or triptolide plus IR. The tumors were measured for volume and weight at the end of the experiment. Tumor tissues were tested for terminal nucleotidyl transferase-mediated nick end labeling (TUNEL) and immunohistochemistry.

RESULTS

The combination of triptolide plus IR reduced cell survival to 21% and enhanced apoptosis, compared with single treatment. In vivo, tumor growth of AsPC-1 xenografts was reduced further in the group treated with triptolide plus IR compared with single treatment. TUNEL and immunohistochemistry of caspase-3 cleavage in tumor tissues indicated that the combination of triptolide plus IR resulted in significantly enhanced apoptosis compared with single treatments.

CONCLUSIONS

Triptolide in combination with ionizing radiation produced synergistic antitumor effects on pancreatic cancer both in vitro and in vivo and seems promising in the combined modality therapy of pancreatic cancer.

Phase II study of cisplatin combined with weekly gemcitabine in the treatment of patients with metastatic pancreatic carcinoma

BACKGROUND/AIMS

Combination therapy of gemcitabine and cisplatin has been reported as an effective regimen for advanced pancreatic cancer. However, the toxicity and synergism are known to depend on the schedule of cisplatin. A phase II study was undertaken to determine the efficacy of a single dose of cisplatin in combination with weekly gemcitabine in patients with metastatic pancreatic carcinoma.

METHODS

Patients with measurable, metastatic pancreatic carcinoma, not locally advanced diseases, were included. The patients were treated with a combination of gemcitabine 1,000 mg/m(2) i.v. over 30 min administered on days 1, 8, and 15 of each cycle and cisplatin 75 mg/m(2) i.v. administered 6 h after gemcitabine infusion on day 1 with adequate prehydration. Response and toxicity were assessed according to World Health Organization criteria.

RESULTS

A total of 52 patients, 5 with recurrent disease after curative operation, were enrolled from January 2000 to March 2004. The objective response rate was 16 of 52 patients (1 complete response and 15 partial response). Disease stabilization was seen in 10 patients (20.8%). The median survival was 11.8 months (95% CI, 10.7-13.0 months), with 76.1% of patients alive at 6 months and 50% alive at 12 months. The median time to progression was 6.1 months (95% CI, 4.16-7.98 months). Major toxicity profiles were thrombocytopenia and neutropenia.

CONCLUSIONS

The modified regimen of a single dose of cisplatin per cycle in combination with weekly gemcitabine appeared to have a more favorable therapeutic index and comparable toxicity profiles.

Antitumor effect of trastuzumab for pancreatic cancer with high HER-2 expression and enhancement of effect by combined therapy with gemcitabine

PURPOSE

The purpose of the present study was to evaluate whether trastuzumab has antitumor effect against pancreatic cancer and whether this effect is concordant with levels of HER-2, which is reportedly overexpressed in pancreatic cancer. We also investigated whether the effect is potentiated in combined therapy with gemcitabine.

EXPERIMENTAL DESIGN

Using immunohistochemistry and FACScan, we analyzed HER-2 expression in 16 pancreatic cancer cell lines. The in vitro antiproliferative effect of trastuzumab, alone and in combination with gemcitabine, was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The in vitro antibody-dependent cell-mediated cytotoxicity of trastuzumab was investigated by (51)Cr release assay. The in vivo antitumor effect of trastuzumab, alone and in combination with gemcitabine, was evaluated in nude mouse xenograft growth. The survival benefit was evaluated in a Capan-1 orthotopic implanted nude mouse model.

RESULTS

HER-2 expression of 2+ or more was observed in 10 and of 3+ in 2 of the 16 cell lines. No in vitro growth-inhibitory effect of trastuzumab was found in any cell line, but trastuzumab induced antibody-dependent cell-mediated cytotoxicity in proportion to HER-2 expression level. Trastuzumab inhibited tumor growth in Capan-1 (HER-2: 3+) xenografts and prolonged survival in the orthotopic model. These effects were increased by combined therapy with gemcitabine. In contrast, trastuzumab exhibited no antitumor effect against PANC-1 (HER-2: 1+) or SW1990 (HER-2: 2+) xenografts.

CONCLUSIONS

The antitumor effect of trastuzumab in pancreatic cancer with high HER-2 expression was shown in vitro and in vivo. Clinical application of trastuzumab is expected in pancreatic cancer with 3+ HER-2 expression.

Sanguinarine induces apoptosis of human pancreatic carcinoma AsPC-1 and BxPC-3 cells via modulations in Bcl-2 family proteins

Pancreatic cancer is associated with low responsiveness to conventional chemotherapies and its incidence nearly equals its death rate. This warrants the development of novel mechanism-based approaches for the management of pancreatic cancer. This study was designed to determine the potential of sanguinarine, a plant alkaloid known to possess strong antimicrobial, anti-inflammatory, and antioxidant activities, against human pancreatic carcinoma cells. Employing human pancreatic carcinoma AsPC-1 and BxPC-3 cells, we specifically evaluated the pro-apoptotic and cell cycle deregulatory effects of sanguinarine and evaluated the involvement of Bcl-2 family proteins and p53 as the mechanism of the biological effects of sanguinarine. Our data demonstrated that sanguinarine (at low concentrations of 0.1-10 microM; for 24 h) treatment to AsPC-1 and BxPC-3 cells resulted in a dose dependent (i) inhibition of viability and growth, (ii) colony formation ability, (iii) induction of apoptosis, and (iv) G0-G1 phase cell cycle arrest. Further, sanguinarine-treatment to AsPC-1 and BxPC-3 cells resulted in a dose dependent (i) increase in pro-apoptotic Bax, Bid and Bak proteins; (ii) decrease in anti-apoptotic Bcl-2 and Bcl-X(L) proteins; and (iii) decrease in p53 with an increase in its phosphorylation. Based on our study, we suggest that sanguinarine may be developed as an agent for the management of pancreatic cancer. Indeed, more in depth studies both in vitro as well as in vivo in appropriate relevant animal models are needed to strengthen this suggestion.

Significant growth inhibition of orthotopic pancreatic ductal adenocarcinoma by CpG oligonucleotides in immunodeficient mice

BACKGROUND/AIMS

The high rate of local recurrence after radical resection of pancreatic ductal adenocarcinoma fosters intensive efforts to develop new approaches for adjuvant treatment. Antisense and modified oligodeoxynucleotides (ODNs) have demonstrated significant tumour growth inhibitory effects in preclinical systems. Our aim was to evaluate the possible therapeutic potential of ODNs containing unmethylated deoxycytidyl-deoxyguanosine dinucleotides (CpG motifs).

METHODOLOGY

For in vitro analysis, [(3)H]thymidine incorporation for DNA synthesis, colorimetric cell vitality assay (EZ4U assay), and DNA fragmentation assay (JAM-[(3)H]thymidine incorporation assay) to test for apoptosis were performed. In vivo testing was done on an orthotopic pancreatic xenotransplantation model using severe combined immunodeficient (SCID) beige and nude mice.

RESULTS

No significant differential effect of either control ODN or CpG-1826 ODN with regard to tumour cell proliferation or induction of apoptosis was observed in vitro. In vivo, ODN-1826 proved to have a significant inhibitory effect (up to 40% reduction of tumour weight) when compared with tumour-bearing animals treated with saline or control ODN. This was accompanied by sevenfold increase in splenomegaly and moderate hepatomegaly. The reduction of tumour weight by ODN-1826 was only slightly more pronounced in nude compared with SCID beige mice.

CONCLUSION

CpG-1826 induces significant growth-inhibitory effects on orthotopic xenotransplanted pancreatic tumours in highly immunodeficient mice, which might be explained by innate immunity mechanisms and possibly a complex interaction of tumour and stroma cells.

Adjuvant treatment of pancreatic carcinoma in a clinically adapted mouse resection model

BACKGROUND

The high rate of local recurrence after radical resection of pancreatic adenocarcinoma fosters intensive efforts to develop new approaches for adjuvant treatment. The established animal models show significant limitations in simulating an adjuvant therapeutic setting. For optimal approximation to the clinical situation we therefore improved a murine orthotopic human xenotransplantation model.

METHODS

Subtotal pancreatectomy in mice was performed after orthotopic inoculation of human pancreatic cancer cells and manifestation of solid tumours. The natural course of disease, tumour growth and metastases were analysed. Gemcitabine as a cytotoxic drug was tested in vitro on the cell line used in this model and the effect of adjuvant treatment with gemcitabine in vivo was investigated.

RESULTS

All tumour-resected animals showed local recurrence. Organ metastases occurred in 67% in resected compared to 25% of non-resected animals. Gemcitabine in vitro was ineffective, but as adjuvant monotherapy resulted in a highly significant reduction of tumour weight and metastatic events.

CONCLUSION

Subtotal pancreatectomy for xenotransplanted pancreatic cancer in SCID beige mice is feasible. Due to high rates of local recurrence and increased organ metastases, this model offers a relevant option for preclinical adjuvant testing, especially as in vitro and in vivo effects of cytotoxic drugs differ enormously.

Phase-II study on stereotactic radiotherapy of locally advanced pancreatic carcinoma

BACKGROUND AND PURPOSE

The majority of patients with pancreatic cancer have advanced disease at the time of diagnosis and are not amenable for surgery. Stereotactic radiotherapy (SRT) may be an alternative treatment for patients with locally advanced disease. The effect of SRT was investigated in the present phase-II trial.

PATIENTS AND METHODS

Twenty-two patients with locally advanced and surgically non-resectable, histological proven pancreatic carcinoma were included into the trial. The patients were immobilized by the Elekta stereotactic body frame (SBF) or a custom made body frame. SRT was given on standard LINAC with standard multi-leaf collimator. Central dose was 15 Gyx3 within 5-10 days.

RESULTS

Evaluation of response was found to be very difficult due to radiation and tumour related tissue reaction. Only two patients (9%) were found to have a partial response (PR), the remaining had no change (NC) or progression (PD) after treatment. Six patients had local tumour progression, but only one patient had an isolated local failure without simultaneous distant metastasis. Median time to local or distant progression was 4.8 months. Median survival time was 5.7 months and only 5% were alive 1 year after treatment. Acute toxicity reported 14 days after treatment was pronounced. There was a significant deterioration of performance status (P=0.008), more nausea (P=0.001) and more pain (P=0.008) after 14 days compared with base-line. However, 8 of 12 patients (66%) improved in performance status, scored less nausea, pain, or needed less analgesic drugs at 3 months after treatment. Four patients suffered from severe mucositis or ulceration of the stomach or duodenum and one of the patients had a non-fatal ulcer perforation of the stomach.

CONCLUSIONS

SRT was associated with poor outcome, unacceptable toxicity and questionable palliative effect and cannot be recommended for patients with advanced pancreatic carcinoma.

Establishment and Characterization of a Pancreatic Carcinoma Cell Line Derived from Malignant Pleural Effusion

BACKGROUND/AIMS

A novel cell line, designated p34, was developed from the malignant pleural effusion of a patient with carcinoma of pancreas. The objective of this work was to characterize this cell line.

METHOD

The in vitro studies included karyotype analysis, immunohistochemistry, XTT cell proliferation assay, analysis of the cell cycle by FACS and cell sensitivity to chemotherapeutic drugs and irradiation. Subcutaneous and intra-spleen inoculations into nude mice were carried out to study the tumorigenicity and the metastatic tendency of this cell line.

RESULTS

The p34 cell line showed typical morphological characteristics of epithelial pancreatic tumor cells. The cells were hyperdiploid with a modal number of 48, and had two markers, deletion in the short arm of chromosome 2 and duplication of the short arm of chromosome 8. The doubling time was 16 h. Subcutaneous inoculation of the cells into nude mice yielded 100% tumorigenicity, and intra-spleen inoculation resulted in extensive intra-abdominal spread. The antiproliferative effect of chemotherapy (gemcitabine, cisplatin, taxol and vinorelbine), chemopreventive agents (celecoxib and curcumin) and radiotherapy showed dose-dependent cytotoxicity.

CONCLUSIONS

This p34 cell line can be used as a new model for studying various aspects of the biology of human pancreatic cancer and potential treatment approaches for the disease.

A Phase II Trial of Raltitrexed (Tomudex®) in Advanced Pancreatic and Biliary Carcinoma

PURPOSE

To evaluate the impact of raltitrexed (Tomudex) on the quality of life in a multicenter, phase II study in advanced pancreatic and biliary carcinomas.

PATIENTS AND METHODS

Forty-six patients with advanced, histologically proven pancreatic (n = 37, 80.4%) or biliary (n = 9, 19.6%) carcinoma received 3 mg/m2 raltitrexed intravenously once every 3 weeks. For the quality of life assessments, EORTC QLQ-C30 was used, and the evaluation of the clinical benefit was performed according to the 4 criteria of the clinical benefit response. All patients were assessed for safety, and 41 patients were evaluable for objective response.

RESULTS

Patients (63% male/37% female) had a mean age of 61.2 years, 71.7% had a PS of 0-1, 78.3% had metastatic disease, and 63% had at least 2 tumoral sites. A total of 176 cycles were administered with a mean of 4 cycles per patient (range 1-12). Three out of 43 patients evaluable for EORTC QLQ-C30 (7.0%; CI(95%) 1.4-19.0%) had a quality of life improvement. Thirty-two patients fulfilled the 4 criteria required to evaluate the clinical benefit response; 5 were responders (15.6%; CI(95%) 5.3-32.8%); 1 patient was a good responder based on both the EORTC questionnaire and the clinical benefit response. Forty-one patients were assessable for response, 3 responded to treatment (response rate: 6.5 %; CI(95%) 1.3-17.9%). Median survival was 4.6 months (CI(95%) 2.9-8.2 months), the 1-year survival rate was 21.8%. The most common grade 3-4 toxicities were neutropenia (8%), leukopenia (8%), thrombopenia (6%), anemia (6%), liver enzyme elevations (11%), asthenia (9%), vomiting (9%), abdominal pain (7%), and phlebitis (6%). One treatment-related death occurred (neutropenic sepsis).

CONCLUSION

Raltitrexed appeared to be generally well tolerated and showed a clinical benefit response and/or quality of life improvement in a limited number of patients.

Magnetic resonance imaging in an orthotopic rat model: blockade of epidermal growth factor receptor with EMD72000 inhibits human pancreatic carcinoma growth

The purpose of our research was to investigate the antiangiogenic effect of the epidermal growth factor receptor monoclonal antibody (anti-EGF-R MAB) EMD72000, in an orthotopic human pancreatic carcinoma model in rats, assessed by magnetic resonance (MR) imaging using angiogenic surrogate markers in comparison with histopathologic findings. Human pancreatic adenocarcinoma cells L3.6pl were injected orthotopically in the pancreas of 12 athymic nude rats. Through a 21-day course, groups of 6 rats were treated intraperitoneally with either EMD72000 or with saline solution for control animals. Dynamic contrast-enhanced MR imaging was performed before and after the treatment to assess microvascular permeability, estimated by the endothelial transfer coefficient (KPS) and fractional plasma volumes (fPV) of the pancreatic tumors. EMD72000-treated animals showed significantly less tumor volume progression (1,080 mm3 +/- 1,244; p = 0.012) and significantly lower values for microvascular permeability (KPS = 4.2 ml min(-1) 100 ml(-1) of tissue +/- 2.8; p = 0.015), fractional plasma volume (fPV = 0.018 ml ml(-1) of tissue +/- .015; p = 0.003) and microvessel density (MVD = 13 +/- 4 (0.159 mm2); p = 0.001) than saline-treated animals (6,544 mm3 +/- 5,202; 9.5 ml min(-1) 100 ml(-1) of tissue +/- 4.3, 0.056 ml ml(-1) of tissue +/- 0.019 and 25 +/- 5 (0.159 mm2), respectively). KPS and fPV values showed moderate positive correlation with MVD (r = 0.5, p = 0.103; r = 0.6, p = 0.065, respectively). Intraperitoneal injection of EMD72000 inhibits orthotopic human pancreatic carcinoma growth in rats. Antiangiogenic effects of anti-EGF-R MAB EMD72000 can be quantified and monitored noninvasively by dynamic MR imaging.

Increased survival, proliferation, and migration in metastatic human pancreatic tumor cells expressing functional CXCR4

In this study, we have evaluated 11 pancreatic tumor cell lines and tumor cells from surgical samples of patients with pancreatic adenocarcinoma for expression of the chemokine receptor CXCR4. Six of 11 cell lines expressed detectable mRNA of CXCR4, with three cell lines (AsPC1, Capan1, and Hs766T) having substantial amounts of transcripts. Expression was higher in lines derived from metastatic lesions compared with those derived from primary tumors. Different inflammatory cytokines did not modify expression, whereas IFN-gamma down-regulated and hypoxia up-regulated CXCR4 transcripts. Transcript expression was associated with surface expression in pancreatic carcinoma cell lines. All surgical carcinoma samples tested expressed higher levels of CXCR4 than normal pancreatic ducts, which were used as reference tissue. The chemokine CXCL12 induced chemotaxis in CXCR4-positive pancreatic carcinoma cell lines, which was inhibited by anti-CXCR4 monoclonal antibody and by the antagonist AMD3100. Transendothelial migration, Matrigel invasion, and activation of matrix metalloproteases were also enhanced by CXCL12. In CXCR4-positive cell lines, CXCL12 stimulated cell proliferation. The cell line Hs766T produces high levels of CXCL12, and addition of the CXCR4 antagonist AMD3100 partially inhibited proliferation, indicating an autocrine loop. Moreover, the addition of exogenous CXCL12 inhibited apoptosis induced by serum starvation. These results indicate that the CXCR4 receptor is frequently expressed in metastatic pancreatic tumor cells. CXCR4 not only stimulates cell motility and invasion but also promotes survival and proliferation. Strategies to target CXCR4 expressed on tumor cells may be of benefit in patients with pancreatic cancer.

Fundamentals of transcription factors and their impact on pancreatic development and cancer

Transcription factors are proteins that regulate gene expression by modulating the synthesis of messenger RNA. Since this process, known as gene transcription, is often the dominant control point in the production of many proteins, transcription factors are key regulators of numerous cellular functions, including secretion, proliferation, differentiation, and apoptosis. Most transcription factors are also the final effectors of signaling pathways that transduce signals from the cell membrane to the nucleus. Therefore alterations in the activity or expression of some transcription factors have a significant impact on the biology of human cells and may lead to the development of diseases. In this article we review this field of research with a particular emphasis on the role of transcription factors in pancreatic development and cancer.

Terminally modified oligodeoxynucleotides directed against p53 in an orthotopic xenograft model: a novel adjuvant treatment strategy for pancreatic ductal carcinoma

OBJECTIVES

Investigation of a terminally modified oligodeoxynucleotide (ODN) directed against p53 mRNA (p53-3' polyethylene glycol-5' tocopherol ODN as a novel drug for pancreatic ductal carcinoma therapy in vitro and in vivo.

METHODS

The impact of lipophilic modifications at the 5' end of p53-directed ODNs on cellular uptake was analyzed in vitro using proliferation assays, fluorescence-activated cell sorting analysis, and confocal laser scanning microscopy. The in vivo effects of p53-PT-ODN on the growth of orthotopically xenografted human pancreatic ductal carcinoma cells (PancTuI) were studied in SCID beige mice. Distribution was examined in vitro and in vivo using Cy3-labeled ODNs.

RESULTS

Terminally modified p53-PT-ODN showed excellent cellular uptake without using transfection reagents. Microscopically detectable levels of p53-PT-ODN were reached in vivo within 3 hours after intraperitoneal injection, even in extraperitoneal organs. At this time, Cy3-labeled p53-PT-ODN was found in solid tumor formations. We observed a significant inhibition of tumor growth (50%) in vivo at low doses of p53-PT-ODN, whereas at high doses, 2 of 9 animals had no detectable tumors at necropsy. When p53-PT-ODN was injected on the day of tumor cell inoculation, the growth inhibition of solid tumors was significantly stronger compared with that with delayed treatment.

CONCLUSIONS

p53-Directed modified ODNs might be of therapeutic value in pancreatic ductal carcinoma, particularly as adjuvant therapy after pancreatic tumor resection.

Extracellular matrix proteins protect pancreatic cancer cells from death via mitochondrial and nonmitochondrial pathways

BACKGROUND AND AIMS

Pancreatic cancer is a very aggressive malignancy. Normal cells die through apoptosis when detached from extracellular matrix (ECM), but the role of ECM in cancer cell survival is poorly understood. Here, we determined the effects of ECM proteins on death responses and underlying signaling pathways in human pancreatic cancer cells.

METHODS

We measured apoptosis and necrosis, caspase activation, and mitochondrial dysfunction in MIA PaCa-2 and PANC-1 pancreatic carcinoma cells both detached and attached to ECM proteins.

RESULTS

Detachment of pancreatic cancer cells from ECM did not induce classic apoptosis, as it does in normal cells, but induced necrosis and apoptosis associated with secondary necrosis. It caused a pronounced mitochondrial depolarization and release of cytochrome c and Smac/DIABLO. However, as different from normal cells, cytochrome c release did not result in downstream caspase activation. Executioner caspases were activated in detached pancreatic cancer cells independent of cytochrome c. Laminin and fibronectin, but not collagen I, markedly increased pancreatic cancer cell survival by inhibiting both mitochondrial dysfunction (leading to inhibition of necrosis) and caspase activity (leading to decreased apoptotic DNA fragmentation).

CONCLUSIONS

ECM proteins greatly protect pancreatic cancer cells from death by mechanisms different from those operating in normal cells. The results suggest ECM proteins and their receptors as potential targets for treatment of pancreatic cancer.

Treatment of pancreatic cancer xenografts with Erbitux (IMC-C225) anti-EGFR antibody, gemcitabine, and radiation

PURPOSE

To investigate treatment of human pancreatic cancer cell lines and xenografts with combinations of Erbitux (IMC-C225) anti-epidermal growth factor receptor (EGFR) antibody, gemcitabine, and radiation.

METHODS AND MATERIALS

BxPC-3 and MiaPaCa-2 human pancreatic carcinoma cells were treated in vitro for 24 h with IMC-C225 (5 microg/mL), then exposed to epidermal growth factor (EGF) (10 mM) for 5 min. Immunoblots were screened for EGFR expression and the ability of IMC-C225 to block EGF-induced tyrosine phosphorylation of EGFR. Cells were treated with IMC-C225 (5 microg/mL) on Day 0, the IC(50) dose of gemcitabine on Day 1 for 24 h, followed by 3 Gy 60Co irradiation on Day 2, or the combination of each agent. For cell proliferation, cells were counted on Day 4, and for apoptosis, cells were stained with annexin V-FITC and propidium iodide, then analyzed by FACS. Cells were treated with the same single or multiple treatments and analyzed in a clonogenic cell survival assay. The effect of IMC-C225, gemcitabine, and radiation on the growth of BxPC-3 and MiaPaCa-2 tumor xenografts was determined. Athymic nude mice bearing established s.c. tumor xenografts of 6-8 mm diameter received 6 weeks of treatment with IMC-C225 (1 mg every 3 days x 6) alone or in combination with gemcitabine (120 mg/kg i.v. every 6 days x 6), and 6 weekly fractions of 3 Gy radiation on the days after gemcitabine administration. Tumor growth was measured with Vernier calipers.

RESULTS

BxPC-3 and MiaPaCa-2 cell lines expressed low levels of EGFR. IMC-C225 inhibited EGF-induced tyrosine phosphorylation of the EGF receptor on both cell lines. Treatment of cells with a combination of IMC-C225 + gemcitabine + radiation produced the highest induction of apoptosis and inhibition of proliferation in vitro. Combination treatment with IMC-C225, gemcitabine, and radiation produced 100% complete regression of MiaPaCa-2 tumors for more than 250 days, and the greatest growth inhibition of BxPC-3 tumors compared to any single or dual treatments.

CONCLUSIONS

The IMC-C225 therapy in combination with gemcitabine chemotherapy and radiation therapy demonstrated statistically significantly greater efficacy over the single and double combination therapies. This form of multimodality treatment shows potential clinical application in the treatment of pancreatic cancer in humans.

Regional chemotherapy

Regional chemotherapy is an interesting treatment option in patients with advanced pancreatic cancer but cannot be considered standard treatment, and it should not be performed outside controlled clinical trials. The real value of regional chemotherapy must be evaluated in larger, randomized trials. New drug combinations may reduce the observed side effects and improve tumor response. Gene therapy with p53 and K-ras modulated herpesviruses may become a palliative treatment option and can be administered easily by regional chemotherapy techniques [23].

Interventional endoscopy, neoadjuvant therapy and the gastroenterologist

With current treatment, survival of greater than 1 year should be anticipated for many patients with pancreatic cancer. Cure rates (5-year survival) of greater than 10% have been achieved even for unresectable disease. Obstructive jaundice is managed successfully with endoscopic placement of a plastic stent early in the evaluation of a patient with suspected regional pancreatic cancer, and a metal wall stent is reserved for patients with known 1997 AJCC stage IVB carcinoma or nonoperative patients. Relief of biliary obstruction allows improvement in liver function and more time to evaluate tumor stage accurately to determine initial treatment (see Fig. 1). A cost-effective algorithm to determine accurate stage and treatment can start with the size of the mass on initial imaging studies. EUS-guided FNA represents a significant improvement over CT scan-guided FNA to make a tissue diagnosis. Small pancreatic masses that would be resected regardless of whether an FNA is positive or negative require only an EUS evaluation to establish an early resectable stage. Tumors reliably staged as unresectable by nonoperative imaging methods including EUS are treated with chemotherapy with or without concurrent radiotherapy because median survival of these patients is 2 years in some series. Tumors can be resected after neoadjuvant chemoradiotherapy. For chronic pain or gastric outlet obstruction not responding or treatable by chemoradiotherapy, endoscopically guided celiac plexus nerve block and stenting improve the quality of life for patients with pancreatic cancer. A team approach is required to achieve the objectives of improved quality of life, prolonged survival, and possible cure for pancreatic cancer. The optimal combination and sequencing of staging methods, including EUS, specialized CT scan, MR imaging, intraoperative findings, and pathologic evaluations, would improve selection of patients for potential curative resection. Interpretations of disease stage based on each of these methods may overlap but are not identical and are operator dependent. Rather than reliance on any single standard, clinical judgment and communication among the team are paramount to providing optimal care for patients with a pancreatic neoplasm.

Early detection of pancreatic cancer in patients with chronic pancreatitis: diagnostic utility of a K-ras point mutation in the pancreatic juice

OBJECTIVE

Point mutations of the K-ras oncogene at codon 12 have been described several months before the onset of pancreatic cancer in isolated cases of chronic pancreatitis (CP). The aim of this study was to evaluate the interest of a prospective follow-up of patients with CP and K-ras mutations at codon 12 in the detection of early pancreatic cancer.

METHODS

From February 1996 to March 1998, 36 patients (mean age 52.6 yr, 31 men, five women) with CP (alcoholic: 61.1%, pancreas divisum: 5.6%, autoimmune: 5.6%, unknown origin: 27.7%) were included and then prospectively monitored (median duration of 22 months) for detection of pancreatic carcinoma. K-ras point mutations were examined by two-step polymerase chain reaction combined with restriction enzyme digestion in pancreatic juice collected during endoscopic retrograde pancreatography.

RESULTS

Ten patients (27.8%) were positive for K-ras mutation. Patients with and without the mutation were not different with respect to age and sex ratio. K-ras mutations were homogeneously distributed according to the etiology (alcoholic vs nonalcoholic) and morphological characteristics (ductal stricture or mass vs none) of CP. A pancreatic carcinoma was discovered at an invasive stage in two patients, respectively at 7 and 17 months after disclosure of a K-ras mutation, versus none in patients without the mutation (p < 0.02).

CONCLUSIONS

Presence of a K-ras gene mutation is not rare in patients with CP and represents an increased risk of developing pancreatic cancer. However, its utility for the detection of early pancreatic cancer remains doubtful in clinical practice.

Relation between smoking and skin cancer

PURPOSE

Tobacco smoking is a risk factor for several cancers. The risk of cutaneous malignancies related to smoking, however, is relatively unknown. We investigated the possible association between smoking and skin cancer.

PATIENTS AND METHODS

A hospital-based case-control study was performed that included 161 patients with squamous cell carcinoma, 301 with nodular basal cell carcinoma, 153 with superficial multifocal basal cell carcinoma, 125 with malignant melanoma, and 386 controls. Information on smoking history was collected in personal interviews. Relative risks were estimated using exposure odds ratios from cross-tabulation and logistic regression.

RESULTS

An association between smoking and squamous cell carcinoma of the skin was found (relative risk, 2.3; 95% confidence interval, 1.5 to 3.6; P: = .0001), with a higher risk for current smokers (relative risk, 3.3; 95% confidence interval, 1.9 to 5.5) than for former smokers (relative risk, 1.9; 95% confidence interval, 1.2 to 3.0). After adjustment for age, sex, and sun exposure, the relative risk of squamous cell carcinoma was 2.0 (95% confidence interval, 1.2 to 3.2; P: = .008). There was a dose-response relationship with number of cigarettes and pipes smoked. No significant association was found between smoking and nodular basal cell carcinoma, superficial multifocal basal cell carcinoma, or malignant melanoma.

CONCLUSION

Tobacco smoking is an independent risk factor for cutaneous squamous cell carcinoma.

Critical role of extracellular signal-regulated kinase (ERK) phosphorylation in novel vitamin K analog-induced cell death

In the present study, we show that 2-(2-hydroxyethylsulfaryl)-3-methyl-1,4-naphthoquinone, or CPD 5, is a potent growth inhibitor for pancreas cancer cell lines (ID(50): 21.4 +/- 3.8, 31.8 +/- 2.7 and 55.2 +/- 4.5 microM for MiaPaCa, Panc-1 and BxPc3, respectively). It induced protein tyrosine phosphor-ylation of hepatocyte growth factor (HGF) receptor (c-Met) or epidermal growth factor receptor (EGFR), which increased progressively to a maximum level at 30 min in Panc-1 cells. The receptor phosphorylation by CPD 5 was indicated to be functional, since these receptors were found to bind with Grb2 or SOS1 protein. CPD 5 was also suggested to induce phosphorylation of external signal-regulated kinase (ERK). EGF induced cell proliferation through ERK phosphorylation, since U0126, which is an inhibitor of ERK phosphorylation, abrogated the increase of cyclin D1 by EGF. HGF increased the amount of p27 protein, suggesting that it is associated with cell differentiation. By contrast, U0126 reduced CPD 5-induced cell death. On two-dimensional electrophoresis, we found an extra type of phospho-ERK, and this was completely and selectively abolished by U0126. These results suggest that ERK phosphorylation, especially the extra spot on two-dimensional gel, is critically associated with CPD 5-mediated cell death.

Value of p53 immunostaining in pancreatico-biliary brush cytology specimens

Brush cytology is routinely used in the assessment of pancreatico-biliary strictures but the technique has limited diagnostic sensitivity in malignant lesions. It has been suggested that ancillary techniques, such as the identification of p53 immunoreactivity, might improve diagnostic accuracy. p53 protein expression was examined in 143 consecutive brush cytology specimens from patients with pancreatic or bile duct strictures and correlated with conventional cytological assessment and clinicopathologic follow-up data. Sixty-three of 89 (70.8%) malignant strictures were identified cytologically while 45 cases (50.6%) were p53 immunoreactive. One case of bile duct adenoma with high-grade dysplasia was reported as consistent with adenocarcinoma cytologically and was p53 negative. There was one false-positive diagnosis with conventional cytology and, in a separate case, with p53 immunostaining. Nineteen specimens (13.3%) were considered atypical cytologically and p53 expression proved accurate in only 12 cases (four immunopositive carcinomas and eight negative benign strictures). In conclusion, p53 immunostaining proved less sensitive than conventional cytology in this series and its routine diagnostic use could not be supported.

Diagnostic and therapeutic approach to pancreatic cancer

Adenocarcinoma of the pancreas ranks fourth as a cause of cancer death in adults in the United States and is the second most common cause of cancer deaths of all GI-related carcinomas. It usually presents late in its course. The clinical features are discussed, with emphasis on those that allow early detection of the disease, as well as a review of diagnostic methods and pre- and perioperative staging, which will allow the appropriate application of surgical and palliative therapeutic modalities. Despite the significant progress that has been made, further research studies are needed to advance our therapeutic approach to this aggressive cancer.

The dominant negative H-ras mutant, N116Y, suppresses growth of metastatic human pancreatic cancer cells in the liver of nude mice

In pancreatic cancer, the mutation of c-K-ras is a critical event of tumor growth and metastasis. We have previously demonstrated a dominant negative effect of N116Y on the growth of pancreatic cancer cells. To evaluate the potential of N116Y for suppressing the metastatic growth of pancreatic tumor cells, we made a replication-deficient recombinant N116Y adenovirus driven by the carcinoembryonic antigen (CEA) promoter (Ad CEA-N116Y). We demonstrated that the expression of N116Y, growth inhibition, and apoptotic death induction were all specific to pancreatic cancer cell lines (PCI-35 and PCI-43) that were promoter positive, whereas no growth retardation was observed in human embryonic pancreas-derived cell line 1C3D3 after Ad CEA-N116Y infection. We examined the effect of Ad CEA-N116Y on the metastatic growth of PCI-43 colonies in liver, which was generated by tumor injection into the spleen of nude mice. The results showed that Ad CEA-N116Y effectively reduced the number of metastatic colonies without any complication by injecting intrasplenically 5 days after tumor cell inoculation. Thus, N116Y can selectively suppress the metastatic growth of pancreatic tumor cell by using the CEA promoter-driven adenovirus vector indicating that N116Y gene therapy may be potentially useful for the treatment of pancreatic cancer patients with liver micrometastasis.

Molecular biology of pancreatic cancer; oncogenes, tumour suppressor genes, growth factors, and their receptors from a clinical perspective

Pancreatic cancer represents the fourth leading cause of cancer death in men and the fifth in women. Prognosis remains dismal, mainly because the diagnosis is made late in the clinical course of the disease. The need to improve the diagnosis, detection, and treatment of pancreatic cancer is great. It is in this type of cancer, in which the mortality is so great and the clinical detection so difficult that the recent advances of molecular biology may have a significant impact. Genetic alterations can be detected at different levels. These alterations include oncogene mutations (most commonly, K-ras mutations, which occur in 75% to more than 95% of pancreatic cancer tissues), tumour suppressor genes alterations (mainly, p53, p16, DCC, etc.), overexpression of growth factors (such as EGF, TGF alpha, TGF beta 1-3, aFGF, bTGF, etc.) and their receptors (i.e., EGF receptor, TGF beta receptor I-III, etc.). Insights into the molecular genetics of pancreatic carcinogenesis are beginning to form a genetic model for pancreatic cancer and its precursors. These improvements in our understanding of the molecular biology of pancreatic cancer are not simply of research interest, but may have clinical implications, such as risk assessment, early diagnosis, treatment, and prognosis evaluation.

[Therapy of pancreatic adenocarcinoma]

BACKGROUND

Despite significant advances in the areas of epidemiology, risk factors, molecular genetics and diagnosis pancreatic carcinoma is characterized by a dismal prognosis and ranks 5th among malignancy-associated deaths. This article attempts to critically review the current literature and analyze therapeutic recommendations based on published evidence. Therapeutic options are based on the stage of the disease.

SURGICAL TREATMENT

Surgical resection with curative intention is feasible only in a minority of patients presenting with locally confined tumor disease. RADIO- AND CHEMOTHERAPY: Adjuvant combined radiochemotherapy might potentially improve survival and can also be considered in unresectable, locally advanced disease. The role of chemotherapy in advanced disease is exclusively palliative. Up to now, no chemotherapeutic regimen has demonstrated convincing impact on survival. Newer substances, such as gemcitabine, appear to be of some value in respect to quality of life. Best supportive care oriented at clinical symptoms remains a cornerstone in the therapeutic concept of patients with pancreatic carcinoma.

CONCLUSION

Development of innovative therapeutic strategies is therefore mandatory.

Abdominal US for diagnosis of pancreatic tumor: prospective cohort analysis

PURPOSE

To elucidate the accuracy of abdominal ultrasonography (US) in the diagnosis of pancreatic tumors.

MATERIALS AND METHODS

In all patients referred for pancreatic US during 1988-1990, data on malignant disease and survival were analyzed by using the Swedish Death and Cancer Registries. Nine hundred nineteen patients were entered into the analysis. In 140 of them, a clinical diagnosis of tumor in the pancreatic area was confirmed within 1 year after US. These tumors were primary pancreatic tumors (n = 102), common bile duct and duodenal cancers (n = 17), and metastases in the pancreatic area (n = 21).

RESULTS

The sensitivity of US in the detection of all tumors in the pancreatic area was 88.6% (124 of 140 patients), which was similar to that for the detection of exocrine pancreatic cancer, 90% (79 of 88 patients). There were nine false-positive US examinations, for a specificity of 98.8% (770 of 779 patients). Systematic sampling of 94 investigations confirmed an association between US accuracy and presence of clinical symptoms of pancreatic cancer. Significant differences in the sensitivity (P < .05) and accuracy (P < .01) of diagnosis were observed between three experienced investigators.

CONCLUSION

Study results support the use of US as a first-line diagnostic examination in patients suspected of having pancreatic tumor. Dependency on the investigator's experience with US mandates continuous evaluation of its performance.

The role of endoscopy in acute recurrent and chronic pancreatitis and pancreatic cancer

Endoscopy plays an important role in the diagnosis and treatment of acute and chronic pancreatitis as well as pancreatic cancer. Sphincterotomy and stone removal in biliary pancreatitis, stone extraction and drainage in chronic pancreatitis, and stent implantation in pancreatic cancer are the predominant procedures. With endoscopy, minimal invasive techniques are at hand to solve urgent and long term problems.

Prognostic factors in nonresectable pancreatic adenocarcinoma: a rationale to design therapeutic trials

OBJECTIVE

Most patients with pancreatic cancer show an advanced tumor at the time of diagnosis. In recent years, new therapies have been developed in such patients, thus forcing the analysis of factors that influence their survival. The present study was aimed at determining the prognostic factors in a series of 134 consecutive patients with pancreatic carcinoma not suitable for surgical resection, due to either locally advanced tumors or metastatic spread.

METHODS

First, 34 epidemiological, clinical, analytical, and tumor-related parameters recruited at admission were included in a univariate analysis of survival by using the Kaplan-Meier method. Those significant variables in the previous step were thereafter introduced in a Cox regression procedure. A prognostic index for calculating the relative risk of death of each patient was also proposed.

RESULTS

The median survival time in the whole series was 3.11 months, the 3, 6, and 12 months probability of survival being 51%, 28%, and 8%, respectively. Eight of 34 variables (jaundice and toxic syndrome at admission, serum cholesterol, iron and alanine aminotransferase concentrations, leukocyte count, baseline performance status, and the presence of distant metastases) were selected in the univariate analysis. Of these eight parameters, the Cox regression analysis identified a preserved baseline performance status (OR = 2.14, 95% CI = 1.49-3.04) and the absence of metastases (OR = 1.34, 95% CI = 1.03-1.73) as the only variables independently associated with a longer survival. Therefore, a prognostic index was constructed allowing the division of patients in three different groups according to their relative risk of death (RRD) = exp (performance status x 0.7589 + presence of metastases x 0.2891).

CONCLUSIONS

The results of the present investigation suggest that baseline performance status and distant metastases should be considered in designing and evaluating any therapeutic trial in patients with nonresectable pancreatic carcinoma.

The p21-Ras signal transduction pathway and growth regulation in human high-grade gliomas

Deregulated p21-Ras function, as a result of mutation, overexpression or growth factor-induced overactivation, contributes to at least 30% of human cancer. This article reviews the potential role of the p21-Ras family of GTPases in the regulation of growth of high-grade gliomas and describes how targeting this oncoprotein clinically may provide a novel strategy to counteract glioma proliferation. The application of strategies directed at selectively opposing the deregulated signal transduction pathway of high-grade gliomas may be of potential therapeutic benefit and may offer a whole new arsenal of antineoplastic agents to be included in the multimodal treatment of these challenging neoplasms.

Pancreatic cancer and fibrinogen storage disease

BACKGROUND

Ductal adenocarcinoma is the most common type of pancreatic carcinoma while squamous, carcinosarcoma, sarcoma, giant cell carcinoma, and clear cell types are all rare. Hepatocellular fibrinogen storage disease is also an uncommon disorder which may be associated with hepatocellular carcinoma. Two cases of pancreatic carcinoma were encountered in a family with fibrinogen storage disease, further raising the possibility of a predilection to malignancy in this unusual disorder. The tumour in one case was of the rare clear cell type. These two cases are the basis for this report.

METHODS

Sections were cut from retrieved paraffin embedded tissue and stained for routine histology. Immunohistochemistry using the avidin-biotin technique was applied for the expression of the markers p53 (D07), carcinoembryonic antigen (CEA), c-erbB-2, epithelial membrane antigen (EMA), and alpha-fetoprotein (AFP).

RESULTS

Both cases were adenocarcinoma of pancreatic ductal origin. The tumour in one case showed features of a clear cell carcinoma. The tumour cells expressed p53, CEA, and EMA immunoreactivity and were negative for c-erbB-2 and AFP.

CONCLUSIONS

Hepatocellular fibrinogen storage disease is rare and has been described in association with chronic hepatitis, cirrhosis, and rarely with hepatocellular carcinoma. This represents the first report of its association with carcinoma outside of the liver.

[Does neoadjuvant radiochemotherapy augment the resectability of pancreatic cancers?]

PURPOSE OF THE STUDY

Pre-operative radiochemotherapy is the most recent therapeutic option in the pre-operative downstaging of pancreatic cancer and in decreasing the rate of positive resection margins. The purpose of the study was to evaluate tolerance and efficacy of pre-operative radiochemotherapy in unresectable pancreatic cancers.

MATERIAL AND METHODS

This study included seven cases of pancreatic cancer considered unresectable. The patients received preoperatively 50 grays within a 5-week period associated with 5 FU and Platin during the 1st and 5th weeks.

RESULTS

After radiochemotherapy, tomodensitometric evaluation showed a minor response in two cases. A pancreatico-duodenectomy could be performed in these two patients without any increase of pre- or post-operative morbidity or mortality.

CONCLUSIONS

The results of the study suggest that preoperative radiochemotherapy may increase pancreatic cancer resectability. This hypothesis should be confirmed by a prospective randomised trial.

[Fight against cancer of the exocrine pancreas: stagnation or progress? The point of view of the Fondation française de cancérologie digestive (FFCD)]

This paper updates recent trends concerning ductal pancreatic cancer. Knowledge of the cellular mechanisms has improved, and new developments in imaging allow a more accurate staging. Although operative mortality sharply decreased during these last 15 years, the prognosis of pancreatic carcinoma remains dismal, due to late diagnosis, as only one out of ten patients is considered for curative resection. Therapeutic research groups, and among them the Fondation française de cancérologie digestive (FFCD), do their best to develop new therapeutic strategies, including post-operative or preferentially pre-operative radio-chemotherapeutic adjuvant treatments, and to improve chemotherapy in metastatic cancers.