FOLFIRINOX versus gemcitabine for metastatic pancreatic cancer

Acinar cell carcinoma of the pancreas: clinical and cytomorphologic characteristics

Acinar cell carcinoma is a rare malignant epithelial neoplasm with predominantly exocrine acinar differentiation and is seen primarily in older men (mean age, 62 years). The presenting symptoms are usually non-specific, and jaundice is often not present. Symptoms relating to the overproduction and release of lipase into the circulation are present in 10-15% of patients. Characteristic cytomorphologic features include a population of cells with minimal pleomorphism, eccentrically placed nuclei with a single prominent nucleoli and moderate hyperchromasia. The cytoplasm is finely granular, and the background may contain granular debris secondary to cytolysis. A significant proportion of the cases also have a minor neuroendocrine component or scattered neuroendocrine cells. Approximately 50% of patients have metastatic disease at presentation, often restricted to the regional lymph nodes and liver. The prognosis is poor, only slightly better than that of pancreatic ductal adenocarcinoma.

TL-118-anti-angiogenic treatment in pancreatic cancer: a case report

Pancreatic cancer is one of the most aggressive malignant tumors. In recent years, little progress has been made in understanding and treatment of the disease. The two most commonly used chemotherapy drugs approved for the treatment of pancreatic cancer are gemcitabine and fluorouracil. Anti-angiogenic treatment is one of the current promising approaches in cancer translational research. Its aim is to inhibit development of new blood vessels and thereby prevent further tumor growth. We present a first description of a pancreatic cancer patient treated with standard chemotherapy and TL-118, an anti-angiogenic combination of 4 drugs that target non-overlapping aspects of the angiogenic process (Provided by Tiltan Pharma Ltd for compassionate use). Our patient, treated with standard chemotherapy combined with TL-118, was diagnosed about 16 months ago and is still considered progression free, while being treated with that combination. Moreover, when the treatment with TL-118 was stopped, there was a clear elevation of tumor marker which dropped again with the renewal of TL-118. This effect was not achieved by gemcitabine treatment alone. Recently, a phase II clinical trial of TL-118 for pancreatic cancer patients that have not yet been treated with chemotherapy was initiated. (Tiltan Pharma Ltd). The study objective is to evaluate the efficacy, safety, and tolerability of TL-118 in gemcitabine-treated metastatic pancreatic cancer patients. This report describes a new approach in treating pancreatic cancer, enabling patients to obtain a longer progression-free survival using this new anti-angiogenic drug combination, added on standard chemotherapy.

Palliation of biliary and duodenal obstruction in patients with unresectable pancreatic cancer: endoscopy or surgery?

Patients with unresectable pancreatic adenocarcinoma often develop biliary and/or duodenal obstruction during the course of their disease. Jaundice, pruritis, nausea and vomiting impact negatively on the quality of life and chemotherapy must often be withheld until these symptoms are resolved. In the past, an open surgical palliative bypass was proposed, but the development of endoprosthetic stents has changed the management of these patients. The success rate for placement of duodenal and biliary stents is greater than 90% with low morbidity. Classical surgical bypass surgery includes biliary-digestive and gastro-jejunal anastomoses. Many studies have compared endoscopic and surgical treatment, and there is a clear advantage to endoscopic treatment in terms of quality of life and cost.

A phase 1b study of trametinib, an oral Mitogen-activated protein kinase kinase (MEK) inhibitor, in combination with gemcitabine in advanced solid tumours

PURPOSE

This phase 1b study determined the safety, tolerability, and recommended phase 2 dose (RP2D) and schedule of trametinib in combination with gemcitabine. Secondary objectives included assessment of clinical activity and steady-state pharmacokinetics.

METHODS

Adults with advanced solid tumours, adequate organ function and Eastern Co-operative Oncology Group performance status (ECOG PS) ⩽ 1 were eligible. Once-daily oral trametinib (1mg, 2mg, 2.5mg) was escalated in a 3+3 design with standard gemcitabine dosing (1000 mg/m(2) IV Days 1, 8, and 15 of 28-day cycles). During expansion, trametinib 2mg was combined with gemcitabine. Pharmacokinetics samples were collected on Day 15 pre-dose and 1, 2, 4 and 6h post-dose; tumour assessments were repeated every two cycles.

RESULTS

Between 8/2009 and 11/2010, 31 patients (pancreas = 11, breast = 6, non-small cell lung cancer (NSCLC) = 4, other = 10) were treated. Dose-limiting toxicities (DLTs) occurred in each cohort, and included febrile neutropenia, transaminase elevation and uveitis. The RP2D was declared as trametinib 2mg daily with standard gemcitabine dosing. Common grade 3/4 toxicities at the RP2D included: neutropenia (38%), thrombocytopenia (19%) and transaminase elevation (14%). Of 10 patients with measurable pancreatic cancer, three partial responses (30%) were documented; two additional patients achieved objective responses (breast, complete response (CR); salivary glands, partial response (PR)). Pharmacokinetics suggested no change in exposures of either drug in combination.

CONCLUSION

Administration of trametinib at its full monotherapy dose of 2mg daily in combination with standard gemcitabine dosing (1000 mg/m(2) IV Days 1, 8, and 15 every 28 days) was feasible. Though most toxicities were manageable, the addition of trametinib may increase gemcitabine-associated myelosuppression. Future studies of this combination will require monitoring to maintain dose and schedule.

Cost-effectiveness of systemic therapies for metastatic pancreatic cancer

PURPOSE

Gemcitabine and capecitabine (gem-cap), gemcitabine and erlotinib (gem-e), and folfirinox (5-fluorouracil-leucovorin-irinotecan-oxaliplatin) are new treatment options for metastatic pancreatic cancer, but they are also more expensive and potentially more toxic than gemcitabine alone (gem). We conducted a cost-effectiveness analysis of these treatment options compared with gem.

METHODS

A Markov model was constructed to examine costs and outcomes of gem-cap, gem-e, folfirinox, and gem in patients with metastatic pancreatic cancer from the perspective of a government health care plan. Ontario health economic and costing data (2010 Canadian dollars) were used. Efficacy data for the treatments were obtained from the published literature. Resource utilization data were derived from a chart review of consecutive metastatic patients treated for pancreatic cancer at Princess Margaret Hospital, Toronto, Ontario, 2008-2009, and supplemented with data from the literature. Utilities were obtained by surveying medical oncologists across Canada using the EQ-5D. Incremental cost-effectiveness ratios (icers) were calculated.

RESULTS

The icers for gem-cap, gem-e, and folfirinox compared with gem were, respectively, CA$84,299, CA$153,631, and CA$133,184 per quality-adjusted life year (qaly). The model was driven mostly by drug acquisition costs. Given a willingness-to-pay (wtp) threshold greater than CA$130,000/qaly, folfirinox was most cost-effective treatment. When the wtp threshold was less than CA$80,000/qaly, gem alone was most cost-effective. The gem-e option was dominated by the other treatments.

CONCLUSIONS

The most cost-effective treatment for metastatic pancreatic cancer depends on the societal wtp threshold. If the societal wtp threshold were to be relatively high or if drug costs were to be substantially reduced, folfirinox might be cost-effective.

STAT5b as molecular target in pancreatic cancer--inhibition of tumor growth, angiogenesis, and metastases

The prognosis of patients suffering from pancreatic cancer is still poor and novel therapeutic options are urgently needed. Recently, the transcription factor signal transducer and activator of transcription 5b (STAT5b) was associated with tumor progression in human solid cancer. Hence, we assessed whether STAT5b might serve as an anticancer target in ductal pancreatic adenocarcinoma (DPAC). We found that nuclear expression of STAT5b can be detected in approximately 50% of DPAC. Blockade of STAT5b by stable shRNA-mediated knockdown showed no effects on tumor cell growth in vitro. However, inhibition of tumor cell motility was found even in response to stimulation with epidermal growth factor or interleukin-6. These findings were paralleled by a reduction of prometastatic and proangiogenic factors in vitro. Subsequent in vivo experiments revealed a strong growth inhibition on STAT5b blockade in subcutaneous and orthotopic models. These findings were paralleled by impaired tumor angiogenesis in vivo. In contrast to the subcutaneous model, the orthotopic model revealed a strong reduction of tumor cell proliferation that emphasizes the meaning of assessing targets in an appropriate microenvironment. Taken together, our results suggest that STAT5b might be a potential novel target for human DPAC.

Prognostic value of CA 19-9, CEA, CRP, LDH and bilirubin levels in locally advanced and metastatic pancreatic cancer: results from a multicenter, pooled analysis of patients receiving palliative chemotherapy

PURPOSE

CA 19-9 is the only established tumor marker in pancreatic cancer (PC); the prognostic role of other serum markers like CEA, CRP, LDH or bilirubin has not yet been defined.

METHODS

We pooled pre-treatment data on CA 19-9, CEA, CRP, LDH and bilirubin levels from two German multicenter randomized phase II trials together with prospective patient data from one high-volume German Cancer Center. Marker levels were assessed locally before the start of palliative first-line therapy for advanced PC and serially during treatment (for CA 19-9 only). Clinical and biomarker data (overall 12 variables) were correlated with the efficacy endpoints time-to-progression (TTP) and overall survival (OS) by using uni- and multivariate Cox models.

RESULTS

Data from 291 patients were included in this pooled analysis; 253 patients (87 %) received treatment within prospective clinical trials. Median TTP in the study cohort was 5.1 months and median OS 9.0 months. In univariate analysis, pre-treatment CA 19-9 (HR 1.55), LDH (HR 2.04) and CEA (HR 1.89) levels were significantly associated with TTP. Regarding OS, baseline CA 19-9 (HR 1.46), LDH (HR 2.07), CRP (HR 1.69) and bilirubin (HR 1.62) were significant prognostic factors. Within multivariate analyses, pre-treatment log [CA 19-9] (as continuous variable for TTP) and log [bilirubin] as well as log [CRP] (for OS) had an independent prognostic value. A CA 19-9 decline of ≥25 % during the first two chemotherapy cycles was predictive for TTP and OS, independent of the applied CA 19-9 assay.

CONCLUSION

Baseline CA 19-9 and CA 19-9 kinetics during first-line chemotherapy are prognostic in advanced PC. Besides that finding other serum markers like CRP, LDH and bilirubin can also provide prognostic information on TTP and OS.

Combined analysis of intratumoral human equilibrative nucleoside transporter 1 (hENT1) and ribonucleotide reductase regulatory subunit M1 (RRM1) expression is a powerful predictor of survival in patients with pancreatic carcinoma treated with adjuvant gemcitabine-based chemotherapy after operative resection

BACKGROUND

Although postoperative adjuvant chemotherapy for pancreatic carcinoma improves survival in some patients, its efficacy varies among individuals. The aim of this study was to determine the usefulness of intratumoral expression of human equilibrative nucleoside transporter 1 (hENT1) and ribonucleotide reductase regulatory subunit M1 (RRM1) as predictive markers of the efficacy of adjuvant gemcitabine-based chemotherapy for pancreatic carcinoma after operative resection.

METHODS

The expression of intratumoral hENT1 and RRM1 was examined immunohistochemically in 109 patients with pancreatic carcinoma who received adjuvant gemcitabine-based chemotherapy after operative resection. Relationships between clinicopathologic factors, including hENT1 and RRM1 expression, and disease-free and overall survival (DFS and OS) were evaluated by univariate and multivariate analyses.

RESULTS

The 5-year DFS and OS rates for the 109 patients were 26% and 31%, respectively. In univariate analysis, both hENT1 and RRM1 expression were significantly associated with DFS (hENT1, P = .004; RRM1, P = .011) and OS (hENT1, P = .001; RRM1, P = .040). In multivariate analysis, both were independent factors for DFS (hENT1, P = .001; RRM1, P = .009) and OS (hENT1, P = .001, RRM1, P = .019). Evaluation of the combination analysis of both was also identified as a powerful independent predictor of DFS (P < .001) and OS (P < .001).

CONCLUSION

Expression of hENT1 and RRM1 is predictive of the efficacy of adjuvant gemcitabine-based chemotherapy for pancreatic carcinoma after operative resection. In addition, their combined analysis has greater predictive value than either factor alone.

Randomized phase III study of gemcitabine plus S-1, S-1 alone, or gemcitabine alone in patients with locally advanced and metastatic pancreatic cancer in Japan and Taiwan: GEST study

PURPOSE

The present phase III study was designed to investigate the noninferiority of S-1 alone and superiority of gemcitabine plus S-1 compared with gemcitabine alone with respect to overall survival.

PATIENTS AND METHODS

The participants were chemotherapy-naive patients with locally advanced or metastatic pancreatic cancer. Patients were randomly assigned to receive only gemcitabine (1,000 mg/m(2) on days 1, 8, and 15 of a 28-day cycle), only S-1 (80, 100, or 120 mg/d according to body-surface area on days 1 through 28 of a 42-day cycle), or gemcitabine plus S-1 (gemcitabine 1,000 mg/m(2) on days 1 and 8 plus S-1 60, 80, or 100 mg/d according to body-surface area on days 1 through 14 of a 21-day cycle).

RESULTS

In the total of 834 enrolled patients, median overall survival was 8.8 months in the gemcitabine group, 9.7 months in the S-1 group, and 10.1 months in the gemcitabine plus S-1 group. The noninferiority of S-1 to gemcitabine was demonstrated (hazard ratio, 0.96; 97.5% CI, 0.78 to 1.18; P < .001 for noninferiority), whereas the superiority of gemcitabine plus S-1 was not (hazard ratio, 0.88; 97.5% CI, 0.71 to 1.08; P = .15). All treatments were generally well tolerated, although hematologic and GI toxicities were more severe in the gemcitabine plus S-1 group than in the gemcitabine group.

CONCLUSION

Monotherapy with S-1 demonstrated noninferiority to gemcitabine in overall survival with good tolerability and presents a convenient oral alternative for locally advanced and metastatic pancreatic cancer.

Gemcitabine plus capecitabine in unselected patients with advanced pancreatic cancer

OBJECTIVES

Gemcitabine in combination with capecitabine (GEMCAP) is a treatment option for patients with advanced pancreatic cancer (APC), but data are lacking concerning outcomes in unselected patients not enrolled to a randomized trial.

METHODS

Baseline demographic, clinical, toxicity, tumor response, and survival data were collected for previously untreated patients with APC receiving off-protocol GEMCAP at a single institution between 2005 and 2009.

RESULTS

Data from 113 patients were included in the study. The mean age was 65 years; 51% of patients had metastatic disease; and 80% were of World Health Organization performance status 0 or 1. Patients received a mean of 20 weeks of chemotherapy. The objective response rate was 9.7%; the median overall survival was 8.7 months (95% confidence interval, 6.7-10.7), and 34% of patients were alive 1 year after starting treatment. Performance status (0 or 1 vs 2) was a significant prognostic factor (P < 0.0001). Grade 3 or 4 adverse events, excluding nonfebrile neutropenia, were experienced by 37 patients (33%), the commonest being lethargy (8%), hand-foot syndrome (8%), diarrhea (7%), thrombocytopenia (4%), and febrile neutropenia (6%).

CONCLUSIONS

Gemcitabine in combination with capecitabine is effective and tolerable in unselected patients with APC, and outcomes are comparable with those of patients receiving GEMCAP in clinical trials.

Chemoradiation therapy: localized esophageal, gastric, and pancreatic cancer

Chemoradiation plays an important role in management of locally advanced gastrointestinal tumors. This article reviews data regarding chemoradiation for tumors of the upper gastrointestinal tract. For esophageal and gastroesophageal junction cancers, chemoradiation is standard of care in the preoperative setting. In gastric cancer, 2 standards have emerged: definitively treating with perioperative chemotherapy alone and using chemoradiation postoperatively. For pancreatic cancer, the benefit of radiation is less well defined. The future of treatment sites lies in trials evaluating new chemotherapy regimens, alternative systemic therapies, and different radiation fractionation schema. Because care of these patients is complex, multimodality team evaluation before treatment is encouraged.

A tissue-engineered subcutaneous pancreatic cancer model for antitumor drug evaluation

The traditional xenograft subcutaneous pancreatic cancer model is notorious for its low incidence of tumor formation, inconsistent results for the chemotherapeutic effects of drug molecules of interest, and a poor predictive capability for the clinical efficacy of novel drugs. These drawbacks are attributed to a variety of factors, including inoculation of heterogeneous tumor cells from patients with different pathological histories, and use of poorly defined Matrigel^®. In this study, we aimed to tissue-engineer a pancreatic cancer model that could readily cultivate a pancreatic tumor derived from highly homogenous CD24⁺CD44⁺ pancreatic cancer stem cells delivered by a well defined electrospun scaffold of poly(glycolide-co-trimethylene carbonate) and gelatin. The scaffold supported in vitro tumorigenesis from CD24⁺CD44⁺ cancer stem cells for up to 7 days without inducing apoptosis. Moreover, CD24⁺CD44⁺ cancer stem cells delivered by the scaffold grew into a native-like mature pancreatic tumor within 8 weeks in vivo and exhibited accelerated tumorigenesis as well as a higher incidence of tumor formation than the traditional model. In the scaffold model, we discovered that oxaliplatin-gemcitabine (OXA-GEM), a chemotherapeutic regimen, induced tumor regression whereas gemcitabine alone only capped tumor growth. The mechanistic study attributed the superior antitumorigenic performance of OXA-GEM to its ability to induce apoptosis of CD24⁺CD44⁺ cancer stem cells. Compared with the traditional model, the scaffold model demonstrated a higher incidence of tumor formation and accelerated tumor growth. Use of a tiny population of highly homogenous CD24⁺CD44⁺ cancer stem cells delivered by a well defined scaffold greatly reduces the variability associated with the traditional model, which uses a heterogeneous tumor cell population and poorly defined Matrigel. The scaffold model is a robust platform for investigating the antitumorigenesis mechanism of novel chemotherapeutic drugs with a special focus on cancer stem cells.

Controversial issues of neoadjuvant treatment in borderline resectable pancreatic cancer

Pancreatic ductal adenocarcinoma is known as one of the most fatal malignant diseases in gastrointestinal system. Approximately 20% of patients are deemed resectable at the time of diagnosis. Preoperative neoadjuvant therapy to the borderline resectable pancreatic cancer (BRPC) has been challenged to achieve down-staging of cancer, to avoid unnecessary major operation if the pancreatic cancer progresses and distant metastasis develops during preoperative treatment, and to avoid delayed adjuvant treatment after major operation due to postoperative complications and poor general condition after major surgery. However, there are some controversial issues influencing the clinical interpretation of surgical and oncologic outcomes of pancreatectomy following neoadjuvant treatment in managing BRPC. This manuscript reviews the current controversial issues in managing BRPC in order to enhance proper understanding the current status and potential role of neoadjuvant treatment in managing BRPC.

Human equilibrative nucleoside transporter 1 and Notch3 can predict gemcitabine effects in patients with unresectable pancreatic cancer

Background:

Pancreatic ductal carcinoma (PDC) is one of the most lethal human carcinomas. Expression patterns of some genes may predict gemcitabine (GEM) treatment efficacy. We examined predictive indicators of survival in GEM-treated patients by quantifying the expression of several genes in pre-treatment endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) samples from patients with PDC.

Methods:

The expressions of human equilibrative nucleoside transporter 1 (hENT1), deoxycitidine kinase, ribonucleoside reductase 1, ribonucleoside reductase 2 and Notch3 in EUS-FNA tissue samples from 71 patients with unresectable PDC were quantified using real-time reverse transcription–polymerase chain reactions and examined for correlations with GEM sensitivity.

Results:

The log-rank test detected no significant differences in overall survival between GEM-treated patients with low and high mRNA levels of all genes examined. However, low Notch3 mRNA expression was significantly associated with longer overall survival in a multivariate analysis for survival (P=0.0094). High hENT1 expression level was significantly associated with a longer time to progression (P=0.039). Interaction tests for GEM administration and hENT1 or Notch3 mRNA expression were statistically significant (P=0.0054 and 0.0047, respectively).

Conclusion:

hENT1 and Notch3 mRNA expressions in EUS-FNA specimens were the key predictive biomarkers of GEM effect and GEM sensitivity in patients with unresectable PDC.

Phase I/II study of albumin-bound nab-paclitaxel plus gemcitabine administered to Chinese patients with advanced pancreatic cancer

PURPOSE

The primary objective of this study was to evaluate the dose-limiting toxicities (DLTs) and identify the maximum-tolerated dose (MTD) and recommended dose of nab-paclitaxel plus gemcitabine as a first-line treatment in Chinese patients with advanced pancreatic ductal adenocarcinoma (PDA).

METHODS

Patients with previously untreated advanced PDA were treated with nab-paclitaxel followed by gemcitabine (1,000 mg/m(2)) administered intravenously for 30 min on days 1 and 8 and repeated every 21 days.

RESULTS

Patients received nab-paclitaxel at the following dose levels: 80 mg/m(2) (n = 3), 100 mg/m(2) (n = 6), and 120 mg/m(2) (n = 12). The DLTs evaluated were elevated alanine aminotransferase and febrile neutropenia. However, there had no two out of three to six patients experienced DLTs, the MTD was not met. A total of 93 cycles were administered. The most common grade 3/4 toxicities were neutropenia (9.52 %), thrombocytopenia (4.76 %), and sensory neuropathy (4.76 %). For 12 patients receiving 120 mg/m(2), the overall response rate and disease control rate were 41.67 and 83.33 %, respectively, and the median progression-free survival and overall survival were 5.23 and 12.17 months, respectively.

CONCLUSIONS

Treatment with albumin-bound nab-paclitaxel (120 mg/m(2)) plus gemcitabine has a favorable safety profile with an encouraging antitumor effect in Chinese patients.

Targeting miR-21 for the therapy of pancreatic cancer

Despite tremendous efforts worldwide from clinicians and cancer scientists, pancreatic ductal adenocarcinoma (PDA) remains a deadly disease for which no cure is available. Recently, microRNAs (miRNAs) have emerged as key actors in carcinogenesis and we demonstrated that microRNA-21 (miR-21), oncomiR is expressed early during PDA. In the present study, we asked whether targeting miR-21 in human PDA-derived cell lines using lentiviral vectors (LVs) may impede tumor growth. We demonstrated that LVs-transduced human PDA efficiently downregulated miR-21 expression, both in vitro and in vivo. Consequently, cell proliferation was strongly inhibited and PDA-derived cell lines died by apoptosis through the mitochondrial pathway. In vivo, miR-21 depletion stopped the progression of a very aggressive model of PDA, to induce cell death by apoptosis; furthermore, combining miR-21 targeting and chemotherapeutic treatment provoked tumor regression. We demonstrate herein for the first time that targeting oncogenic miRNA strongly inhibit pancreatic cancer tumor growth both in vitro and in vivo. Because miR-21 is overexpressed in most human tumors; therapeutic delivery of miR-21 antagonists may still be beneficial for a large number of cancers for which no cure is available.

Inhibiting the growth of pancreatic adenocarcinoma in vitro and in vivo through targeted treatment with designer gold nanotherapeutics

Background

Pancreatic cancer is one of the deadliest of all human malignancies with limited options for therapy. Here, we report the development of an optimized targeted drug delivery system to inhibit advanced stage pancreatic tumor growth in an orthotopic mouse model.

Method/Principal Findings

Targeting specificity in vitro was confirmed by preincubation of the pancreatic cancer cells with C225 as well as Nitrobenzylthioinosine (NBMPR - nucleoside transporter (NT) inhibitor). Upon nanoconjugation functional activity of gemcitabine was retained as tested using a thymidine incorporation assay. Significant stability of the nanoconjugates was maintained, with only 12% release of gemcitabine over a 24-hour period in mouse plasma. Finally, an in vivo study demonstrated the inhibition of tumor growth through targeted delivery of a low dose of gemcitabine in an orthotopic model of pancreatic cancer, mimicking an advanced stage of the disease.

Conclusion

We demonstrated in this study that the gold nanoparticle-based therapeutic containing gemcitabine inhibited tumor growth in an advanced stage of the disease in an orthotopic model of pancreatic cancer. Future work would focus on understanding the pharmacokinetics and combining active targeting with passive targeting to further improve the therapeutic efficacy and increase survival.

Enhancing sorafenib-mediated sensitization to gemcitabine in experimental pancreatic cancer through EMAP II

Background

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive human malignancies and tends to be relatively resistant to conventional therapies. Activated Ras oncogene mutations are found in up to 90% of PDAC, leading to activation of the Ras/Raf/MEK/ERK signaling pathway. Sorafenib is a multikinase inhibitor of the Ras/Raf/MEK/ERK pathway and of tumor angiogenesis. Endothelial monocyte activating polypeptide II (EMAP) enhances gemcitabine effects in PDAC. Antitumor activity of sorafenib was evaluated in combination with gemcitabine (Gem) and the antiangiogenic agent EMAP in experimental PDAC.

Methods

Cell proliferation and protein expression were analyzed by WST-1 assay and Western blotting. Animal survival studies were performed in murine PDAC xenografts.

Results

Sorafenib decreased phospho-MEK, phospho-ERK1/2, phospho-p70S6K and phospho-4EBP-1 expression in PDAC cells. Sorafenib inhibited in vitro proliferation of all four PDAC cell lines tested. Additive effects on cell proliferation inhibition were observed in the gemcitabine-sorafenib combination in PDAC cells, and in combinations of sorafenib or EMAP with gemcitabine in endothelial (HUVEC) and fibroblast (WI-38) cells. Sorafenib, alone or in combination with gemcitabine and EMAP, induced apoptosis in HUVECs and WI-38 cells as observed via increased expression of cleaved poly (ADP-ribose) polymerase-1 (PARP-1) and caspase-3 proteins. Compared to controls (median survival: 22 days), animal survival increased after Gem therapy (29 days) but not in sorafenib (23 days) or EMAP therapy alone (25 days). Further increases in survival occurred in combination therapy groups Gem+sorafenib (30 days, p=0.004), Gem+EMAP (33 days, p=0.002), and Gem+sorafenib+EMAP (36 days, p=0.004), but not after the sorafenib+EMAP combination (24 days).

Conclusions

These findings demonstrate that the addition of a polymechanistic antiangiogenic agent such as EMAP can enhance the combination treatment effects of sorafenib and cytotoxic PDAC therapy.

Pharmacological ascorbate with gemcitabine for the control of metastatic and node-positive pancreatic cancer (PACMAN): results from a phase I clinical trial

BACKGROUND

Treatment for pancreatic cancer with pharmacological ascorbate (ascorbic acid, vitamin C) decreases tumor progression in preclinical models. A phase I clinical trial was performed to establish safety and tolerability of pharmacological ascorbate combined with gemcitabine in patients with biopsy-proven stage IV pancreatic adenocarcinoma.

DESIGN

Nine subjects received twice-weekly intravenous ascorbate (15-125 g) employing Simon's accelerated titration design to achieve a targeted post-infusion plasma level of ≥350 mg/dL (≥20 mM). Subjects received concurrent gemcitabine. Disease burden, weight, performance status, hematologic and metabolic laboratories, time to progression and overall survival were monitored.

RESULTS

Mean plasma ascorbate trough levels were significantly higher than baseline (1.46 ± 0.02 vs. 0.78 ± 0.09 mg/dL, i.e., 83 vs. 44 μM, p < 0.001). Adverse events attributable to the drug combination were rare and included diarrhea (n = 4) and dry mouth (n = 6). Dose-limiting criteria were not met for this study. Mean survival of subjects completing at least two cycles (8 weeks) of therapy was 13 ± 2 months.

CONCLUSIONS

Data suggest pharmacologic ascorbate administered concurrently with gemcitabine is well tolerated. Initial data from this small sampling suggest some efficacy. Further studies powered to determine efficacy should be conducted.

Stereotactic body radiation therapy with concurrent full-dose gemcitabine for locally advanced pancreatic cancer: a pilot trial demonstrating safety

Background

Concurrent chemoradiation is a standard option for locally advanced pancreatic cancer (LAPC). Concurrent conventional radiation with full-dose gemcitabine has significant toxicity. Stereotactic body radiation therapy (SBRT) may provide the opportunity to administer radiation in a shorter time frame with similar efficacy and reduced toxicity. This Pilot study assessed the safety of concurrent full-dose gemcitabine with SBRT for LAPC.

Methods

Patients received gemcitabine, 1000 mg/m² for 6 cycles. During week 4 of cycle 1, patients received SBRT (25 Gy delivered in five consecutive daily fractions of 5 Gy prescribed to the 75-83% isodose line). Acute and late toxicities were assessed using NIH CTCAE v3. Tumor response was assessed by RECIST. Patients underwent an esophagogastroduodenoscopy at baseline, 2, and 6 months to assess the duodenal mucosa. Quality of life (QoL) data was collected before and after treatment using the QLQ-C30 and QLQ-PAN26 questionnaires.

Results

Between September 2009 and February 2011, 11 patients enrolled with one withdrawal during radiation therapy. Patients had grade 1 to 2 gastrointestinal toxicity from the start of SBRT to 2 weeks after treatment. There were no grade 3 or greater radiation-related toxicities or delays for cycle 2 of gemcitabine. On endoscopy, there were no grade 2 or higher mucosal toxicities. Two patients had a partial response. The median progression free and overall survival were 6.8 and 12.2 months, respectively. Global QoL did not change between baseline and immediately after radiation treatment.

Conclusions

SBRT with concurrent full dose gemcitabine is safe when administered to patients with LAPC. There is no delay in administration of radiation or chemotherapy, and radiation is completed with minimal toxicity.

Persistent activation of pancreatic stellate cells creates a microenvironment favorable for the malignant behavior of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most common malignant tumors with poor prognosis due to extremely high malignancy, low rate of eligibility for surgical resection and chemoradiation resistance. Increasing evidence indicate that the interaction between activated pancreatic stellate cells (PSCs) and PDAC cells plays an important role in the development of PDAC. By producing high levels of cytokines, chemotactic factors, growth factors and excessive extracellular matrix (ECM), PSCs create desmoplasia and a hypoxic microenvironment that promote the initiation, development, evasion of immune surveillance, invasion, metastasis and resistance to chemoradiation of PDAC. Therefore, targeting the interaction between PSCs and PDAC cells may represent a novel therapeutic approach to advanced PDAC, especially therapies that target PSCs of the pancreatic tumor microenvironment.

Clinical outcomes of chemotherapy for diabetic and nondiabetic patients with pancreatic cancer: better prognosis with statin use in diabetic patients

OBJECTIVES

The aim of this study was to clarify the impact of diabetes mellitus (DM) as well as antidiabetic, antihypertensive, and antihyperlipidemic medications such as metformin and statins on survival in patients with advanced pancreatic cancer receiving chemotherapy.

METHODS

We retrospectively reviewed the medical records of 250 patients with advanced pancreatic cancer receiving chemotherapy. Multivariate analyses of prognostic factors for survival were performed both in overall population and in subgroups with and without DM.

RESULTS

Diabetes mellitus was diagnosed in 124 patients (50%) who had less distant metastasis and more hypertension. Thirty patients received statin for hyperlipidemia. Overall survival was 13.3 versus 10.0 months with and without DM (P = 0.084), but hazard ratio of DM was 1.05 (P = 0.758) in the multivariate analysis. Subgroup analysis of diabetic patients, but not in non-diabetic patients, demonstrated use of statins (hazard ratio, 0.40; P = 0.010) as a prognostic factor, as well as distant metastasis, performance status, combination therapy with gemcitabine and S-1, and use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. No antidiabetic medications were prognostic factors.

CONCLUSIONS

Neither DM nor antidiabetic treatment had prognostic impact on advanced pancreatic cancer. Statin use was associated with better survival in the diabetic patients.

Evidence for treatment and survival disparities by age in pancreatic adenocarcinoma: a population-based analysis

OBJECTIVES

Studies demonstrate safety and survival benefits of surgical resection in older individuals with pancreatic adenocarcinoma. We investigated treatment disparities by age.

METHODS

The Surveillance, Epidemiology, and End Results database for survival and treatment of pancreatic adenocarcinoma between 1983 and 2007 stratified by age: younger than 50 years, between 50 and 70 years, or older than 70 years. Kaplan-Meier curves and Cox proportional hazards models were used for survival differences, and logistic regression models were used for treatment disparities and the decision to refuse surgery.

RESULTS

A total of 45,509 patients had microscopically confirmed pancreatic adenocarcinoma. Of these, 7374 (16%) received surgery and 9842 (22%) received radiation. Younger patients were more likely to receive both surgery and radiation. The prevalence of surgery decreased from 21% for those younger than 50 years to 19% for those between 50 and 70 years to 13% for those older than 70 years (P < 0.001). Radiation decreased from 28% to 25% to 17% (P < 0.001). Overall survival decreased with increasing age at diagnosis, 10.4 months (age <50 years) to 9.1 months (age 50-70 years) to 6.4 months (age >70 years) controlling for stage, sex, race, radiation, and surgery (P < 0.001). Increasing age negatively predicted the odds of receiving both surgery and radiation and increased the likelihood of refusing surgery.

CONCLUSIONS

Treatment disparities exist by age despite advances in radiation and surgical treatment. Increased treatment in the elderly will increase overall survival from pancreatic adenocarcinoma.

Increased radiosensitivity and radiothermosensitivity of human pancreatic MIA PaCa-2 and U251 glioblastoma cell lines treated with the novel Hsp90 inhibitor NVP-HSP990

Background and purpose

Heat shock Protein 90 (Hsp90) is a molecular chaperone that folds, stabilizes, and functionally regulates many cellular proteins involved in oncogenic signaling and in the regulation of radiosensitivity. It is upregulated in response to stress such a heat. Hyperthermia is a potent radiosensitizer, but induction of Hsp90 may potentially limit its efficacy. Our aim was to investigate whether the new Hsp90 inhibitor NVP-HSP990 increases radiosensitivity, thermosensitivity and radiothermosensitivity of human tumor cell lines.

Material and methods

U251 glioblastoma and MIA PaCa-2 pancreatic carcinoma cells were used. To determine clonogenic survival, colony forming assays were performed. Cell viability and proliferation were assesed by Trypan blue staining. Cell cycle and apoptosis analyses were performed by flow cytometry. DAPI staining was used to detect mitotic catastrophe.

Results

NVP-HSP990 increased the thermosensitivity, radiosensitivity and radio-thermosensitivity of both cell lines in clonogenic assays. 72 hours after irradiation with 4 Gy, a significant reduction in cell number associated with considerable G2/M acumulation and mitotic catastrophe as well as cell death by apoptosis/necrosis was observed.

Conclusions

Treatment with NVP-HSP990 strongly sensitized U251 and MIA PaCa-2 cells to hyperthermia and ionizing radiation or combination thereof through augmentation of G2/M arrest, mitotic catastrophe and associated apoptosis.

Histone deacetylase inhibitors and pancreatic cancer: Are there any promising clinical trials?

Pancreatic cancer, although not very frequent, has an exceptionally high mortality rate, making it one of the most common causes of cancer mortality in developed countries. Pancreatic cancer is difficult to diagnose, allowing few patients to have the necessary treatment at a relatively early stage. Despite a marginal benefit in survival, the overall response of pancreatic cancer to current systemic therapy continues to be poor, and new therapies are desperately needed. Histone deacetylase (HDAC) enzymes play an important role in the development and progression of cancer and HDAC inhibitors (HDACIs) have been shown to induce differentiation and cell cycle arrest, activate the extrinsic or intrinsic pathways of apoptosis, and inhibit invasion, migration and angiogenesis in different cancer cell lines. As a result of promising preclinical data, various HDACIs are being tested as either monotherapeutic agents or in combination regimens for both solid and hematological malignancies. Vorinostat was the first HDACI approved by the Food and Drug Administration for patients with cutaneous T-cell lymphoma. The use of HDACIs in clinical trials, in pretreated and relapsed patients suffering from advanced pancreatic cancer is discussed. Unfortunately, clinical data for HDACIs in patients with pancreatic cancer are inadequate, because only a few studies have included patients suffering from this type of neoplasm and the number of pancreatic cancer patients that entered HDACIs phase II/III trials, among others with advanced solid tumors, is very limited. More studies recruiting patients with pancreatic cancer remain to determine the efficiency of these therapies.

Response evaluation following neoadjuvant treatment of pancreatic cancer patients

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive human neoplastic entities, with a very poor prognosis characterized by a high mortality rate and short survival. This is due both to its aggressive biological behaviour and the high incidence of locally advanced stages at the time of the initial diagnosis. The limits of resectability and the role of neoadjuvant (radio) chemotherapy for PDAC management are still unclear. A recently published article by Kats et al compared the radiological, surgical and histopathological results of 129 patients with borderline resectable tumors undergoing neoadjuvant treatment followed by surgery. Although post-neoadjuvant treatment imaging implied a low response rate, a high rate of complete resections was achieved. This seems to confirm that, though radiology has made a significant progress in defining locally advanced PDAC, there is place for further improvement. In particular, the differentiation between radiotherapy-induced scarring/fibrosis and cancer-associated desmoplasia remains a clinical/radiological challenge. Though selection of patients with occult systemic disease is possible with neoadjuvant treatment, downstaging does not seem to occur frequently. Thus, development of novel, more aggressive (radio) chemotherapy regimens is required to improve prognosis of patients with locally unresectable but not systemically micro-metastasized tumors.

Complete pathological remission of locally advanced, unresectable pancreatic cancer (LAPC) after intensified neoadjuvant chemotherapy

BACKGROUND

Unresectable locally advanced pancreatic cancer (LAPC) has an extremely poor prognosis. Results of neoadjuvant (radio-)chemotherapy approaches aiming at achieving resectability are currently not satisfactory.

CASE REPORT

We report the case of a 67-year-old woman with histologically confirmed pancreas carcinoma that was not resectable on first surgical exploration who achieved a well-documented complete pathological remission (pCR). The carcinoma became resectable after consecutive neoadjuvant treatment with nanoparticle albumin-bound (nab)-paclitaxel/gemcitabine and FOLFIRINOX chemotherapy regimens.

CONCLUSION

This is the first reported LAPC case in which neoadjuvant chemotherapy alone has been shown to lead to demonstrated pCR. CA19-9 levels, but not imaging criteria, were useful for response prediction and timing of the Whipple's procedure. The findings in this case suggest possible conceptual changes in the treatment approach for LAPC, and indicate that the new effective chemotherapy regimens should be integrated into clinical trials for LAPC.

CXCR2: a target for pancreatic cancer treatment?

INTRODUCTION

Pancreatic cancer, a leading cause of cancer deaths worldwide, is very aggressive and has minimally effective treatment options. For those who have no surgical options, medical treatments are limited. The chemokine receptor CXCR2 has become the subject of much interest recently because of multiple studies indicating its involvement in cancer and inflammatory conditions. Research now indicates that CXCR2 and its ligands are intimately involved in tumor regulation and growth and that inhibition of its function shows promising results in multiple cancer types, including pancreatic cancer.

AREAS COVERED

In this study, the authors review basic molecular and structural details of CXCR2, as well as the known functions of CXCR2 and several of its ligands in inflammation and cancer biology with specific attention to pancreatic cancer. Then the future possibilities and questions remaining for pharmacological intervention against CXCR2 in pancreatic cancer are explored.

EXPERT OPINION

Many current inhibitory strategies already exist for targeting CXCR2 in vitro as well as in vivo. Clinically speaking, CXCR2 is an exciting potential target for pancreatic cancer; however, CXCR2 is functionally important for multiple processes and therapeutic options would benefit from further work toward understanding of these roles as well as structural and target specificity.

Molecular guided therapy for advanced pancreatic cancer patients with PI3K activated mutation: vision or illusion?

Despite a modern validated regimen of chemotherapy, advanced pancreatic adenocarcinoma remains the fourth most common cause of cancer-related death worldwide. The phosphoinositide 3-kinase pathway (PI3K)/Akt/mammalian target of rapamycin (mTOR) is a major signaling pathway that may be activated in advanced pancreatic cancer. To highlight the potential interest of this targetable pathway in selected advanced pancreatic cancer patients, we report herein a patient with an activated PI3K mutation who was treated in a phase I trial evaluating a treatment combination including an mTOR inhibitor.

Inflammatory networks and immune surveillance of pancreatic carcinoma

Cancer-associated inflammation plays an important role in restraining anti-tumor immunity, particularly in pancreatic ductal adenocarcinoma (PDA) for which a massive infiltration of immunosuppressive leukocytes into the tumor stroma is an early and consistent event in oncogenesis. Intratumoral effector T cells are rare. This pathophysiology is in contrast to many other solid tumors for which infiltration of effector T cells is often prominent, associated with improved clinical outcomes, and mechanistically contributes to tumor immunoediting that ultimately can mediate immune escape. In PDA, increasing evidence suggests that the ras oncogene drives an inflammatory program that establishes immune privilege in the tumor microenvironment. Indeed, PDA cells might remain intrinsically sensitive to T cell killing because they have never been exposed to T cell selective pressure in vivo. In support of this hypothesis, recent studies demonstrate that derailing immune suppressive pathways in the PDA microenvironment, such as tumor derived GM-CSF, facilitates T-cell mediated tumor rejection. These findings carry major implications for the development of novel, combination immunotherapies for pancreatic cancer.

Molecular biology of adenocarcinoma of the pancreatic duct, current state and future therapeutic avenues

Pancreatic adenocarcinoma is a lethal disease; currently surgery offers five years survival of less than 5%. Any improvement in the outcome is likely to be through novel therapeutic agents that will target the genetic machinery of the cell. Knowledge of genetic alterations in the process of carcinogenesis is expanding rapidly, the targeted therapy, however, is progressing slowly. Pancreatic adenocarcinoma displays a variety of molecular changes that evolve exponentially with time and lend the cancer cells their ability not only to survive, but also to invade the surrounding tissues and metastasise to distant sites. These changes involve genetic alteration in oncogenes, cancer suppressor genes, changes in cell cycle, pathways of apoptosis and also changes in epithelial to mesenchymal transition. Monotherapeutic targeted agents seem(s) to have limited effect on cancer cells. The near future is likely to show an improvement in the treatment outcome, which is likely to be a result of the combination of targeted agents with surgery and chemotherapy.

Current evidence for histone deacetylase inhibitors in pancreatic cancer

Pancreatic cancer is one of the most aggressive human cancers, with more than 200 000 deaths worldwide every year. Despite recent efforts, conventional treatment approaches, such as surgery and classic chemotherapy, have only slightly improved patient outcomes. More effective and well-tolerated therapies are required to reverse the current poor prognosis of this type of neoplasm. Among new agents, histone deacetylase inhibitors (HDACIs) are now being tested. HDACIs have multiple biological effects related to acetylation of histones and many non-histone proteins that are involved in regulation of gene expression, apoptosis, cell cycle progression and angiogenesis. HDACIs induce cell cycle arrest and can activate the extrinsic and intrinsic pathways of apoptosis in different cancer cell lines. In the present review, the main mechanisms by which HDACIs act in pancreatic cancer cells in vitro, as well as their antiproliferative effects in animal models are presented. HDACIs constitute a promising treatment for pancreatic cancer with encouraging anti-tumor effects, at well-tolerated doses.

Frequency and intensity of postoperative surveillance after curative treatment of pancreatic cancer: a cost-effectiveness analysis

BACKGROUND

Few data exist to guide oncologic surveillance following curative treatment of pancreatic cancer. We sought to identify a rational, cost-effective postoperative surveillance strategy.

METHODS

We constructed a Markov model to compare the cost-effectiveness of 5 postoperative surveillance strategies. No scheduled surveillance served as the baseline strategy. Clinical evaluation and carbohydrate antigen (CA) 19-9 testing without/with routine computed tomography and chest X-ray at either 6- or 3-month intervals served as the 4 comparison strategies of increasing intensity. We populated the model with symptom, recurrence, treatment, and survival data from patients who had received intensive surveillance after multimodality treatment at our institution between 1998 and 2008. Costs were based on Medicare payments (2011 US dollars).

RESULTS

The baseline strategy of no scheduled surveillance was associated with a postoperative overall survival (OS) of 24.6 months and a cost of $3837/patient. Clinical evaluation and CA 19-9 assay every 6 months until recurrence was associated with a 32.8-month OS and a cost of $7496/patient, with an incremental cost-effectiveness ratio (ICER) of $5364/life-year (LY). Additional routine imaging every 6 months incrementally increased total cost by $3465 without increasing OS. ICERs associated with clinic visits every 3 months without/with routine imaging were $127,680 and $294,696/LY, respectively. Sensitivity analyses changed the strategies' absolute costs but not the relative ranks of their ICERs.

CONCLUSIONS

Increasing the frequency and intensity of postoperative surveillance of patients after curative therapy for pancreatic cancer beyond clinical evaluation and CA 19-9 testing every 6 months increases cost but confers no clinically significant survival benefit.

Chemoradiation in patients with isolated recurrent pancreatic cancer - therapeutical efficacy and probability of re-resection

Background

In the present retrospective analysis we analysed the therapeutic outcome of a set of patients, who were treated with chemoradiation (CRT) for recurrent pancreatic cancer (RPC) in a single institution.

Patients and Methods

Forty-one patients had a history of primary resection for pancreatic cancer. In case of an unresectable recurrency patients were treated with CRT at our institution between 2002 and 2010 with a median dose of 48.4 Gy (range 39.6–54 Gy). Concurrent chemotherapy regimes included Gemcitabine (GEM) in 37/41 patients (90%) and Fluorouracil (FU) or Capecitabine (CAP) in 4/41 patients (10%). Patients were re-evaluated after CRT with computed tomography and/or explorative laparotomy. During re-resection or laparotomy 15 patients received an additional intraoperative radiotherapy (IORT) with a median dose of 15 Gy (range 12–15 Gy). Median age was 65 years (range 39–76 years) and there were 26 male and 15 female patients.

Results

The median overall survival (mOS), local control (LC) and progression-free survival (PFS) were 16.1, 13.8 and 6.9 months respectively for all patients after the first day of CRT. Re-resection was possible in five patients (12%) and a complete remission (CR) as defined by tumor-free biopsy was seen in 6 patients (15%). When re-resection could be achieved after CRT mOS was improved to 28.3 months (n = 5 patients, 95%-CI 10.2 – 46.3 months). Patients receiving IORT had a significantly improved mOS compared to no IORT (p = 0.034). Fifteen patients (37%) experienced a local tumour progression and main site of distant metastasis was the liver (11 patients, 27%).Overall treatment-related toxicity was mild, grade III hematologic toxicity was observed in 11 patients (27%).

Conclusion

In summary we observed a good therapeutic response with mild to moderate toxicity levels for CRT in RPC. Overall survival and PFS were clearly improved in case of induction of a complete remission (tumor-free biopsies) or after achieving a re-resection, thus providing a curative intended therapy even in case of disease recurrence.

Octreotide prophylaxis is not beneficial for biochemical activity and clinical severity of postoperative pancreatic fistula after pancreatic surgery

BACKGROUND

Prospective randomized trials indicate that prophylactic octreotide treatment does not decrease the incidence of postoperative pancreatic fistula (POPF). The aim of this study was to analyze if octreotide prophylaxis could decrease the severity grade of POPFs after pancreatic surgery.

METHOD

Seventy-eight of 684 patients undergoing pancreatic resection with POPF were included in the study. Prophylactic octreotide treatment was started immediately after surgery and was performed in 22 patients, whereas 56 patients had no octreotide treatment and served as controls. Lipase activity was measured in the abdominal drainage on postoperative days (POD) 3, 5 and 7. Primary endpoints of the study were clinical severity of the POPF and lipase activity in the drainage.

RESULTS

There was no significant difference concerning length of postoperative hospital stay. Lipase activity in the abdominal drainage was not influenced by octreotide prophylaxis at POD 5 or 7 compared to POD 3. Multivariate analysis showed that the risk to develop a type B or C fistula in the octreotide group was independent of the kind of operation and the consistency of the pancreas (RR = 3.4; CI = 1.0-11.7; p = 0.050 and RR = 6.3; CI = 1.4-29.6; p = 0.019).

CONCLUSION

Octreotide prophylaxis after pancreatic surgery has no beneficial effect on clinical severity of POPF.

The prognostic role of time to diagnosis and presenting symptoms in patients with pancreatic cancer

BACKGROUND

The aim of this study was to investigate the prognostic role of diagnostic delay and clinical presentation (regarding pain, jaundice, and weight loss) in pancreatic carcinoma.

METHODS

One hundred and seventy patients with pancreatic cancer were diagnosed and treated in the decade 2001-2010 (100 males and 70 females, with a mean age of 65.8 years [range, 36-91]). Patients were staged with spiral computed tomography and 75% were found to have advanced disease (28 stage III, 99 stage IV disease). Ductal adenocarcinoma was diagnosed in 147 cases, other subtypes of carcinoma in the remaining 23. Fifty patients were operated with radical intent, 19 had palliative surgery, 101 were considered inoperable because of advanced disease or heavy anesthesiologic risk; 31 of these inoperable patients underwent biliary decompression by insertion of an endoluminal or percutaneous stent. Gemcitabine-containing regimens were administered to 143 patients and radiotherapy was combined in 19. Overall and relative survival were the parameters studied. Multivariate analysis was performed by multiple regressions applied to proportional-hazards model.

RESULTS

From all the clinical, pathological and therapeutical factors evaluated the statistically significant ones were time to diagnosis and surgery. Among symptoms pain was related to the shortest mean time to diagnosis, weight loss to the longest, with corresponding differences in survival. These differences of observed survival were substantially confirmed in terms of relative survival.

CONCLUSIONS

The poor prognosis of pancreatic carcinoma seems to depend, in part, on diagnostic delay and this, in turn, is influenced by the type of presenting symptoms.

Clinically meaningful responses to sequential gemcitabine-based chemotherapy regimens in a patient with metastatic pancreatic cancer

Pancreatic cancer exhibits profound chemoresistance resulting either from pre-existing (intrinsic) mechanisms, or from anticancer drug treatment itself (acquired chemoresistance). We present the case of a patient with pancreatic adenocarcinoma metastatic to the liver who experienced clinical, radiographic and tumor marker response to three lines of gemcitabine-based chemotherapy. The regimens included: 8 cycles of gemcitabine and oxaliplatin (GEMOX), 8 cycles of gemcitabine, docetaxel and capecitabine (GTX) and more than 3 cycles of gemcitabine and nab-paclitaxel, with an exceptional response 2 years from the initiation of chemotherapy for metastatic pancreatic cancer.

Comparison of survival of patients with metastases from known versus unknown primaries: survival in metastatic cancer

BACKGROUND

Cancer of unknown primary site (CUP) is considered an aggressive metastatic disease but whether the prognosis differs from metastatic cancers of known primary site is not known. Such data may give insight into the biology of CUP and the metastatic process in general.

METHODS

6,745 cancer patients, with primary metastatic cancer at diagnosis, were identified from the Swedish Cancer Registry, and were compared with 2,881 patients with CUP. Patients were diagnosed and died between 2002 and 2008. The influence of the primary site, known or unknown, on survival in patients with metastases at specific locations was investigated. Hazard ratios (HRs) of death were estimated for several sites of metastasis, where patients with known primary sites were compared with CUP patients.

RESULTS

Overall, patients with metastatic cancers with known primary sites had decreased hazards of death compared to CUP patients (HR = 0.69 [95% CI = 0.66-0.72]). The exceptions were cancer of the pancreas (1.71 [1.54-1.90]), liver (1.58 [1.36-1.85]), and stomach (1.16 [1.02-1.31]). For individual metastatic sites, patients with liver or bone metastases of known origin had better survival than those with CUP of the liver and bone. Patients with liver metastases of pancreatic origin had an increased risk of death compared with patients with CUP of the liver (1.25 [1.06-1.46]). The median survival time of CUP patients was three months.

CONCLUSIONS

Patients with CUP have poorer survival than patients with known primaries, except those with brain and respiratory system metastases. Of CUP sites, liver metastases had the worst prognosis. Survival in CUP was comparable to that in metastatic lung cancer. The aggressive behavior of CUP may be due to initial immunosuppression and immunoediting which may allow accumulation of mutations. Upon escape from the suppressed state an unstoppable tumor spread ensues. These novel data on the epidemiology of the metastatic process at the population level demonstrated large survival differences in organ defined metastases depending on the original cancer.

Combination chemotherapy of serine protease inhibitor nafamostat mesilate with oxaliplatin targeting NF-κB activation for pancreatic cancer

In this study, we assessed if nafamostat mesilate may enhance anti-tumor effects of oxaliplatin on Panc-1 cells and pancreatic cancer mouse model. In combination treatment with nafamostat mesilate and oxaliplatin, NF-κB activation was inhibited by suppressing IκBα phosphorylation, and caspase-8-mediated apoptosis was more prominent than that treated with oxaliplatin alone, both in vitro and in vivo. Nafamostat mesilate reduced proliferation rate of Panc-1 cells as compared with oxaliplatin alone in vitro and enhanced oxaliplatin-induced tumor growth inhibition in vivo. Combination chemotherapy using nafamostat mesilate and oxaliplatin induces synergistic cytotoxicity in pancreatic cancer and could be a novel strategy for treatment.

Investigational therapies targeting the ErbB (EGFR, HER2, HER3, HER4) family in GI cancers

INTRODUCTION

Gastrointestinal (GI) malignancies account for nearly one-fourth of all cancer-related deaths in the United States and approximately 30% of all cancer-related deaths worldwide. Use of combination cytotoxic therapy offers a modest improvement in survival, but the prognosis and long-term survival of most patients with GI cancer remains poor. In certain GI malignancies, therapies that target members of the HER family of receptors have positively impacted patient care.

AREAS COVERED

In this review, we discuss the significance of the HER family of receptors in esophagogastric, hepatobiliary, pancreatic, and colorectal cancers and explain the rationale supporting the use of monoclonal antibodies (mAbs) and small molecule tyrosine kinase inhibitors (TKIs) to inhibit HER activation and downstream events that contribute to tumor proliferation, migration, and survival.

EXPERT OPINION

Despite recent advances, the treatment of GI cancers remains challenging. Therapies targeting the HER family of receptors have been extensively studied in these malignancies with inconsistent results. The rationale behind varied tumor responses with these agents remains uncertain. We believe that additional studies are needed to identify biomarkers that could help identify a population of patients who would be more responsive to a given therapy.

The pancreas cancer microenvironment

Pancreatic ductal adenocarcinoma (PDA) is a common and lethal malignancy resulting in more than 250,000 deaths per year worldwide. Despite extensive efforts, cytotoxic and targeted therapies have provided only limited efficacy for patients with PDA to date. One contributing factor to the failure of systemic therapies may be the abundant tumor stromal content that is the characteristic of PDA. The PDA stroma, aptly termed the tumor microenvironment, occupies the majority of the tumor mass, and consists of a dynamic assortment of extracellular matrix components and nonneoplastic cells including fibroblastic, vascular, and immune cells. Recent work has revealed that the PDA stroma supports tumor growth and promotes metastasis and simultaneously serves as a physical barrier to drug delivery. Accordingly, methods that alter stromal composition or function, for instance interference with the vasculature via Notch/Hedgehog pathway inhibition or relief of vascular compression by hyaluronidase, are under active investigation. Here, we will review our current understanding of the PDA tumor microenvironment, and highlight opportunities for further exploration that may benefit patients.

Hyaluronan, fluid pressure, and stromal resistance in pancreas cancer

Pancreatic ductal adenocarcinomas (PDAs) are notoriously aggressive and resistant to treatment. They distinguish themselves further by their robust fibroinflammatory, or desmoplastic, stromal reaction and degree of hypovascularity. Recent findings have revealed multiple mechanisms of stromal complicity in disease pathogenesis and resistance. In this review, we focus on altered physicomechanics as one mechanism of what we term as ‘stromal resistance’ in PDA. Extremely high interstitial fluid pressures and a dense extracellular matrix combine to limit the delivery and distribution of therapeutic agents. We discuss the genesis and consequences of altered fluid dynamics in PDA and strategies to restore them.

Multidisciplinary management of pancreatic cancer

Pancreatic cancer (pancreatic adenocarcinoma) remains one of the deadliest malignancies in the western hemisphere despite improved surgical technique, chemotherapy, and radiation therapy. The appropriate management of this malignancy should incorporate multiple treatment modalities for optimal opportunity for cure. Recent trials with a variety of treatment techniques confer improved survival of patients with pancreatic cancer, even in the metastatic setting. In this review, the importance of multidisciplinary management of pancreatic cancer based on disease stage is discussed.

Targeted degradation of KRAS by an engineered ubiquitin ligase suppresses pancreatic cancer cell growth in vitro and in vivo

KRAS is an attractive pancreatic ductal adenocarcinoma (PDAC) therapeutic target. E3 ligase is thought to be the component of the ubiquitin conjugation system that is directly responsible for substrate recognition. In this study, an engineered E3 ubiquitin ligase (RC-U) was generated to target the KRAS oncoprotein for ubiquitination and degradation. The engineered E3 ubiquitin ligases (RC-U) were constructed (pRC-U and lentivirus-expressing RC-U). After transfecting the pRC-U plasmid into human pancreatic cancer cells, KRAS expression levels were determined. KRAS expression was also evaluated in cells transfected with pRC-U and treated with MG-132 or cycloheximide. Interactions between RC-U and KRAS as well as whether RC-U could ubiquitinate KRAS were investigated. Extracellular signal-regulated kinase 1/2 (ERK1/2) and phosphorylated ERK 1/2 (pERK1/2) levels were examined in pancreatic cancer cells transfected with pRC-U. The effects of RC-U on pancreatic cancer cell growth were assessed. RC-U decreased KRAS protein levels. After pRC-U transfection, KRAS stability was increased in the presence of MG-132. HEK 293T cells were transfected with a mutant KRAS construct together with pRC-U and incubated with cycloheximide to inhibit new protein synthesis. The exogenous mutant KRAS oncoprotein was degraded more quickly. RC-U can bind KRAS and KRAS can be ubiquitinated by RC-U. pERK1/2 protein levels were decreased. RC-U resulted in reduced cell proliferation in vitro and in vivo. KRAS destruction by RC-U occurred through a ubiquitin-dependent, proteasome-mediated degradation pathway. RC-U inhibited pancreatic cancer cell growth in vitro and in vivo.