A phase II study of nab-paclitaxel plus ramucirumab for the second-line treatment of patients with metastatic gastroesophageal cancer

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Background: Nab-paclitaxel (NP) is a protein-stabilized formulation of paclitaxel, US FDA approved for treatment of metastatic breast cancer, advanced/metastatic non-small cell lung cancer and metastatic adenocarcinoma of the pancreas. Ramucirumab (R) is an antibody targeting vascular epithelial growth factor receptor 2 (VEGFR-2) approved for treatment of gastric or gastroesophageal (GE) adenocarcinoma in combination with paclitaxel as 2nd line treatment. This phase II study evaluated the efficacy of NP and R for pts with metastatic GE cancer. Methods: Pts with metastatic GE adenocarcinoma were treated with 125 mg/m2 NP on days 1, 8, and 15, and 8 mg/kg R on days 1 and 15 of each 28-day cycle. Pts continued study treatment (tx) until intolerable toxicity, disease progression (PD), or withdrawal of consent. Restaging occurred every 2 cycles. The primary objective was progression-free survival (PFS); secondary objectives were response rate (RR), time to progression (TTP), overall survival (OS) and toxicity. Results: 65 pts were enrolled between 05/15 and 12/18: median age 63 yrs (35-86), 75% male, 71% ECOG 1. Primary tumor sites were stomach (37%), GE junction (35%), and esophagus (28%). 83% were stage IV at initial diagnosis. 29% were HER2+ at study entry. 57% had 1st line chemo, 40% chemo + targeted agent and 3% chemo + immunotherapy. Median tx duration was 13 weeks (.1-55) for NP and 12 weeks (.1-54) for R; at data cutoff 2 pts remained on tx.60% discontinued due to PD; 17% due to AE. 43% and 23% had AE-related dose reductions of NP and R, respectively; 8% and 6% were on day 15. 58% had dose interruptions of R due to AE; 42% on day 15. Median PFS was 3.8 months (CI 95% 3.4, 4.8); median TTP 4.5 months (CI 95% 3.5, 6.3); and median OS 8.8 months (CI 95% 6.1, 11.3). RR was 15% (CI 95% 6.6, 24.2); disease control rate was 68% (CI 95% 56.3, 79.1). Most common tx related AEs were neutropenia (55%), fatigue (40%), peripheral neuropathy (37%), anorexia and mucositis (26% each). Conclusions: There were no unexpected toxicity findings with NP and R in pts with GE cancers. Compared to historical controls, outcomes in this study were similar to those seen in the Western population of pts who received paclitaxel plus R. Clinical trial information: NCT02317991.

A Randomized, Double-Blinded, Phase II Trial of Gemcitabine and Nab-Paclitaxel Plus Apatorsen or Placebo in Patients with Metastatic Pancreatic Cancer: The RAINIER Trial

LESSONS LEARNED

The addition of the heat shock protein 27 (Hsp27)-targeting antisense oligonucleotide, apatorsen, to a standard first-line chemotherapy regimen did not result in improved survival in unselected patients with metastatic pancreatic cancer.Findings from this trial hint at the possible prognostic and predictive value of serum Hsp27 that may warrant further investigation.

BACKGROUND

This randomized, double-blinded, phase II trial evaluated the efficacy of gemcitabine/nab-paclitaxel plus either apatorsen, an antisense oligonucleotide targeting heat shock protein 27 (Hsp27) mRNA, or placebo in patients with metastatic pancreatic cancer.

METHODS

Patients were randomized 1:1 to Arm A (gemcitabine/nab-paclitaxel plus apatorsen) or Arm B (gemcitabine/nab-paclitaxel plus placebo). Treatment was administered in 28-day cycles, with restaging every 2 cycles, until progression or intolerable toxicity. Serum Hsp27 levels were analyzed at baseline and on treatment. The primary endpoint was overall survival (OS).

RESULTS

One hundred thirty-two patients were enrolled, 66 per arm. Cytopenias and fatigue were the most frequent grade 3/4 treatment-related adverse events for both arms. Median progression-free survival (PFS) and OS were 2.7 and 5.3 months, respectively, for arm A, and 3.8 and 6.9 months, respectively, for arm B. Objective response rate was 18% for both arms. Patients with high serum level of Hsp27 represented a poor-prognosis subgroup who may have derived modest benefit from addition of apatorsen.

CONCLUSION

Addition of apatorsen to chemotherapy does not improve outcomes in unselected patients with metastatic pancreatic cancer in the first-line setting, although a trend toward prolonged PFS and OS in patients with high baseline serum Hsp27 suggests this therapy may warrant further evaluation in this subgroup.

[CD69 expression on T cell surface in patients with obstructive sleep apnea hypopnea syndrome]

Objective:To investigate the detection and significance of T cell CD69 expression in peripheral blood of patients with obstructive sleep apnea hypopnea syndrome (OSAHS).Method:According to AHI, 81 OSAHS patients diagnosed by PSG were divided into 3 groups: light, medium and heavy, with 27 cases in each group; 27 patients without OSAHS as control group. Flow cytometry was used to detect the expression rate of CD69 in T cells, to analyze the correlation between the expression rate of CD69 on T cells and the gender, age, BMI, and PSG index.Result:①The CD69 expression rate of T cells in peripheral blood of OSAHS patients with snoring degree increases gradually (P< 0.05); Comparison between the two shows that there was no significant difference in CD69 expression rate on T cells between the control group and the mild group (t= 1.649, P> 0.05); there were significant differences between the other groups (P< 0.05). ②The CD69 expression rate of T cells in peripheral blood of OSAHS patients has no correlation with BMI, age and gender (P> 0.05), were positively correlated with AHI, negatively correlated with LSaO₂ (P< 0.01). ③The CD69 expression rate of T cells and AHI in 27 cases of severe OSAHS patients with a comprehensive treatment has significantly reduced, LSaO₂ increased significantly (P< 0.01).Conclusion:Increased expression of CD69 in peripheral blood T cells may be one of the mechanisms of OSAHS complicated with cardiovascular disease. Detection of CD69 expression rate in T cells for reflecting the degree of disease in patients with OSAHS, assessment of risk of cardiovascular damage, have certain clinical significance.

Updated efficacy, safety, and biomarker analyses of STEAM, a randomized, open-label, phase II trial of sequential (s) and concurrent (c) FOLFOXIRI-bevacizumab (BV) vs FOLFOX-BV for first-line (1L) treatment (tx) of patients with metastatic colorectal cancer (mCRC)

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Background: STEAM (NCT01765582) assessed efficacy and safety of 1L cFOLFOXIRI-BV and sFOLFOXIRI-BV vs FOLFOX-BV. Updated efficacy, safety, and exploratory biomarker data are reported. Methods: 280 tx-naive pts with mCRC were randomized 1:1:1 to BV-containing (5 mg/kg q2w) arms (cFOLFOXIRI, sFOLFOXIRI [alternating FOLFOX and FOLFIRI every 4 weeks {q4w}], or FOLFOX) in a 4–6 month (mo) induction phase, followed by maintenance. Primary objectives include progression-free survival (PFS). Secondary objectives include overall survival (OS). Tumor-relevant biomarker evaluations were exploratory. Results: Median PFS significantly improved and median OS showed a positive trend with cFOLFOXIRI-BV vs FOLFOX-BV. PFS significantly improved with cFOLFOXFIRI-BV vs FOLFOX-BV in BRAF wild type (WT); there was a positive trend in RAS WT and mutant (MUT) pts; no tx difference observed in BRAF MUT pts. In the safety pop., (n = 271), 88% had Grade ≥ 3 tx emergent AEs: 91% cFOLFOXIRI-BV; 87% sFOLFOXIRI-BV; 86% FOLFOX-BV. Conclusions: Improved PFS and a positive trend in OS were observed for cFOLFOXIRI-BV vs FOLFOX-BV. A positive PFS trend was seen in RAS WT and MUT pts, with significantly improved PFS in BRAF WT. The small number of BRAF MUT pts precluded estimation of tx effects. AEs for all 3 txs were consistent with previous reports. Clinical trial information: NCT01765582. [Table: see text]

RAINIER: A randomized, double-blinded, placebo-controlled phase II trial of gemcitabine (gem) plus nab-paclitaxel (nab-P) combined with apatorsen (A) or placebo (Pl) in patients (pts) with metastatic pancreatic cancer (mPC)

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Background: Heat shock protein 27 (Hsp27) is over-expressed in PC, enabling tumor growth and metastasis. A is an antisense oligonucleotide that binds to Hsp27 mRNA and inhibits production of Hsp27 protein. This randomized phase II trial evaluates the efficacy of gem/nab-P plus A or Pl in pts with mPC. Methods: Pts with untreated mPC were randomized 1:1 to Arm A (gem, nab-P, A) or Arm B (gem, nab-P, Pl). 3 loading doses of 600mg A IV or Pl IV were given, then 600 mg A or Pl weekly with chemotherapy in 28 day cycles. Both arms received gem 1000mg/m2 IV, nab-P 125mg/m2 IV days 1, 8, and 15. Restaging was every 2 cycles. Serum Hsp27 levels were collected at baseline and on treatment. Primary endpoint compared overall survival (OS); secondary endpoints were progression free survival (PFS), response rate (RR), CA 19-9 response, and toxicity. Results: 132 pts were randomized: median age 66 yrs, 57% male, 47% ECOG 0. Demographics were similar for both arms. 36% of pts on Arm A and 48% of pts Arm B discontinued due to progressive disease, and 24% and 14% due to adverse events (AEs). There was a higher incidence of ≥Grade (G) 4 and serious adverse events (SAEs) in Arm A. The most frequently reported G 3/4 treatment-related AEs were anemia (20%), neutropenia (17%), and fatigue (16%) on Arm A and anemia (27%), neutropenia (19%), and thrombocytopenia (13%) on Arm B. Overall RR was 18% on each arm. With a median f/u of 9.1 mos, median PFS and OS are 2.7 and 5.2 mos on Arm A and 3.8 and 6.9 mos on Arm B (p=NS). Correlative analyses between Hsp27 expression and clinical outcomes will be presented. In a statistical model using only Arm B data, 3 base attributes, ECOG >0, liver mets, and neutrophil levels had a strong prognostic relationship to OS. Conclusions: This study showed no improvement in clinical outcomes adding A to gem plus nab-p. G 4 AEs and SAEs were increased with A. We await analysis for Hsp 27 and CA 19-9 levels and further analysis to identify any pt subgroup who might have benefited from the experimental treatment. Clinical trial information: NCT01844817.

Phase 2 trial of oxaliplatin plus capecitabine (XELOX) as second-line therapy for patients with advanced pancreatic cancer

BACKGROUND

To the authors' knowledge, there is no established second-line chemotherapy for patients with pancreatic cancer who have received gemcitabine-based therapy. A phase 2 trial was conducted to explore the efficacy of capecitabine and oxaliplatin (XELOX) in patients with advanced pancreatic cancer previously who were treated with gemcitabine.

METHODS

Patients aged < or = 65 years who had an Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 to 1 received oxaliplatin at a dose of 130 mg/m(2) given on Day 1 and capecitabine at a dose of 1000 mg/m(2) twice daily for 14 days. For patients aged >65 years or with an ECOG PS of 2, the oxaliplatin dose was 110 mg/m(2) on Day 1 and the capecitabine dose was 750 mg/m(2) twice daily for 14 days. The treatment was repeated every 3 weeks. Tumor measurements were performed every 9 weeks and the primary study objective was 6-month overall survival.

RESULTS

The study enrolled 41 patients. Of the 39 evaluable patients, 1 patient had a partial response and 10 patients demonstrated stable disease. The Kaplan-Meier estimate of the overall median survival was 23 weeks (95% confidence interval [95% CI], 17.0-31.0 weeks). Progression-free survival was 9.9 weeks (95% CI, 9.6-14.5 weeks). The 6-month and 1-year survival rates were 44% (95% CI, 31%-62%) and 21% (95% CI, 11%-38%), respectively. The most common grade 3-4 nonhematologic toxicity was fatigue (toxicity was graded using the National Cancer Institute Common Toxicity Criteria [version 2.0]).

CONCLUSIONS

The combination of capecitabine and oxaliplatin is active in gemcitabine-pretreated patients with advanced pancreatic cancer, especially in patients with a good PS and those who have responded to first-line chemotherapy.

Novel therapies for pancreatic adenocarcinoma

Despite advances in our understanding of the molecular and genetic basis of pancreatic cancer, the disease remains a clinical challenge. Gemcitabine, the standard chemotherapy for pancreatic cancer, offers modest improvement of tumor-related symptoms and marginal advantage of survival. New approaches, alone and in combination with gemcitabine, are being developed to combat this cancer. In this article we review the current status of investigations into several classes of agents: matrix metalloproteinase inhibitors; farnesyl transferase inhibitors; epidermal growth factor receptor inhibitors, including monoclonal antibodies and tyrosine kinase inhibitors; cyclooxygenase-2 inhibitors, and others. The scientific rationale, mechanism of action, and clinical trial data for these novel agents are discussed.

Patterns of self-reported symptoms in pancreatic cancer patients receiving chemoradiation

Pancreatic cancer is a lethal disease characterized by multiple disease-related symptoms. Chemoradiation therapy is a standard of treatment for locally advanced pancreatic cancer. Although shown to prolong survival, there is little information about treatment-related symptoms or the palliative benefits of chemoradiation. We assessed symptoms of patients with locally advanced pancreatic cancer receiving chemoradiation to determine the prevalence, and co-occurrence, of symptoms and to identify the extent to which symptoms interfered with function. Forty-eight patients were treated with chemoradiation on a Phase I protocol. Patients received radiotherapy (50.4 Gy in 28 fractions), capecitabine (median dose 825 mg/m(2) twice daily), and bevacizumab (2.5-10 mg/kg). Symptom severity and its interference with function were prospectively assessed (at presentation, during, and after chemoradiation) in 43 consenting patients using the M.D. Anderson Symptom Inventory. Results showed that 95% of patients reported at least one of the 13 symptoms assessed at presentation. The most commonly reported symptoms of moderate to severe (>or=5 on a 0-10 scale) intensity at presentation were lack of appetite (24%), pain (19%), fatigue (19%), and sleep disturbance (10%). We observed an increase in patients reporting moderate to severe fatigue, nausea, and sleep disturbance during chemoradiation. McNemar tests for paired binary observations showed the proportion of patients reporting moderate to severe symptoms significantly (P<0.001) decreased after chemoradiation at 94 days follow-up (lack of appetite=7%, pain=7%, fatigue=13%, sleep disturbance=7%). This study demonstrates the feasibility and usefulness of symptom assessment in chemoradiation protocols. Future studies with larger cohorts are needed to further characterize multiple symptoms associated with chemoradiation.

Borderline resectable pancreatic cancer: definitions, management, and role of preoperative therapy

With recent advances in pancreatic imaging and surgical techniques, a distinct subset of pancreatic tumors is emerging that blurs the distinction between resectable and locally advanced disease: tumors of "borderline resectability." In our practice, patients with borderline-resectable pancreatic cancer include those whose tumors exhibit encasement of a short segment of the hepatic artery, without evidence of tumor extension to the celiac axis, that is amenable to resection and reconstruction; tumor abutment of the superior mesenteric artery involving <180 degrees of the circumference of the artery; or short-segment occlusion of the superior mesenteric vein, portal vein, or their confluence with a suitable option available for vascular reconstruction because the veins are normal above and below the area of tumor involvement. With currently available surgical techniques, patients with borderline-resectable pancreatic head cancer are at high risk for a margin-positive resection. Therefore, our approach to these patients is to use preoperative systemic therapy and local-regional chemoradiation to maximize the potential for an R0 resection and to avoid R2 resections. In our experience, patients with favorable responses to preoperative therapy (radiographical evidence of tumor regression and improvement in serum tumor marker levels) are the subset of patients who have the best chance for an R0 resection and a favorable long-term outcome.

Phase II Placebo-Controlled Randomized Discontinuation Trial of Sorafenib in Patients With Metastatic Renal Cell Carcinoma

Purpose

This phase II randomized discontinuation trial evaluated the effects of sorafenib (BAY 43-9006), an oral multikinase inhibitor targeting the tumor and vasculature, on tumor growth in patients with metastatic renal cell carcinoma.

Patients and Methods

Patients initially received oral sorafenib 400 mg twice daily during the initial run-in period. After 12 weeks, patients with changes in bidimensional tumor measurements that were less than 25% from baseline were randomly assigned to sorafenib or placebo for an additional 12 weeks; patients with ≥ 25% tumor shrinkage continued open-label sorafenib; patients with ≥ 25% tumor growth discontinued treatment. The primary end point was the percentage of randomly assigned patients remaining progression free at 24 weeks after the initiation of sorafenib.

Results

Of 202 patients treated during the run-in period, 73 patients had tumor shrinkage of ≥ 25%. Sixty-five patients with stable disease at 12 weeks were randomly assigned to sorafenib (n = 32) or placebo (n = 33). At 24 weeks, 50% of the sorafenib-treated patients were progression free versus 18% of the placebo-treated patients (P = .0077). Median progression-free survival (PFS) from randomization was significantly longer with sorafenib (24 weeks) than placebo (6 weeks; P = .0087). Median overall PFS was 29 weeks for the entire renal cell carcinoma population (n = 202). Sorafenib was readministered in 28 patients whose disease progressed on placebo; these patients continued on sorafenib until further progression, for a median of 24 weeks. Common adverse events were skin rash/desquamation, hand-foot skin reaction, and fatigue; 9% of patients discontinued therapy, and no patients died from toxicity.

Conclusion

Sorafenib has significant disease-stabilizing activity in metastatic renal cell carcinoma and is tolerable with chronic daily therapy.

Transforming growth factor alpha expression drives constitutive epidermal growth factor receptor pathway activation and sensitivity to gefitinib (Iressa) in human pancreatic cancer cell lines

The epidermal growth factor receptor (EGFR) is considered an important therapeutic target in pancreatic cancer, but it is currently impossible to identify those patients who are most likely to benefit from EGFR-directed therapy. We examined the biological effects of the EGFR tyrosine kinase inhibitor gefitinib (ZD1839, Iressa) in a panel of nine human pancreatic cancer cell lines. The drug strongly inhibited DNA synthesis and induced low levels of apoptosis at clinically relevant concentrations in a subset of three of the lines (L3.6pl, BxPC3, and Cfpac1). Sensitivity to gefitinib correlated directly with ligand [transforming growth factor-alpha (TGF-alpha)] expression (r(2) = 0.71, P = 0.004) but not with surface EGFR expression. The gefitinib-sensitive cells displayed constitutive baseline EGFR phosphorylation, whereas the gefitinib-resistant cells did not. Exposure to gefitinib or a small interfering RNA construct specific for TGF-alpha reversed the constitutive EGFR phosphorylation and downstream target [extracellular signal-regulated kinases (ERK), AKT] phosphorylation in the gefitinib-sensitive cells but had no effects on ERK or AKT phosphorylation in gefitinib-resistant cells. Baseline EGFR phosphorylation was lower in a subclone of L3.6pl selected for low TGF-alpha expression, and these cells were also resistant to gefitinib-mediated growth inhibition. Gefitinib blocked the growth of tumor xenografts derived from L3.6pl cells but had no effect on the growth of tumors derived from EGFR-independent MiaPaCa-2 cells. Together, our data show that TGF-alpha expression identifies a subset of human pancreatic cancer cells that is dependent on EGFR signaling in vitro and in vivo. Quantification of TGF-alpha expression may therefore represent an effective means of identifying EGFR-responsive primary tumors.

Chemotherapy regimen predicts steatohepatitis and an increase in 90-day mortality after surgery for hepatic colorectal metastases

PURPOSE

Chemotherapy before resection of hepatic colorectal metastases (CRM) may cause hepatic injury and affect postoperative outcome.

PATIENTS AND METHODS

Four hundred six patients underwent hepatic resection of CRM between 1992 and 2005. Pathologic review of the nontumorous liver was performed using established criteria for steatosis, steatohepatitis, and sinusoidal injury. The effect of chemotherapy and liver injury on perioperative outcome was analyzed.

RESULTS

One hundred fifty-eight patients (38.9%) received no preoperative chemotherapy, whereas 248 patients (61.1%) did. The median duration of chemotherapy was 16 weeks (range, 2 to 70 weeks). Chemotherapy consisted of fluoropyrimidine-based regimens (fluorouracil [FU] alone, 15.5%; irinotecan plus FU, 23.1%; and oxaliplatin plus FU, 19.5%) and other therapy (3.0%). On pathologic analysis, 36 patients (8.9%) had steatosis, 34 (8.4%) had steatohepatitis, and 22 (5.4%) had sinusoidal dilation. Oxaliplatin was associated with sinusoidal dilation compared with no chemotherapy (18.9% v 1.9%, respectively; P < .001; odds ratio [OR] = 8.3; 95% CI, 2.9 to 23.6). In contrast, irinotecan was associated with steatohepatitis compared with no chemotherapy (20.2% v 4.4%, respectively; P < .001; OR = 5.4; 95% CI, 2.2 to 13.5). Patients with steatohepatitis had an increased 90-day mortality compared with patients who did not have steatohepatitis (14.7% v 1.6%, respectively; P = .001; OR = 10.5; 95% CI, 2.0 to 36.4).

CONCLUSION

Steatohepatitis is associated with an increased 90-day mortality after hepatic surgery. In patients with hepatic CRM, the chemotherapy regimen should be carefully considered because the risk of hepatotoxicity is significant.

Phase I trial evaluating the safety of bevacizumab with concurrent radiotherapy and capecitabine in locally advanced pancreatic cancer

PURPOSE

To study the safety of bevacizumab with capecitabine-based chemoradiotherapy.

PATIENTS AND METHODS

Patients with inoperable pancreatic adenocarcinoma received bevacizumab 2 weeks before radiotherapy (50.4 Gy treating the primary tumor and gross adenopathy), every 2 weeks during radiotherapy (12 patients each at 2.5, 5.0, 7.5, and 10 mg/kg), and after radiotherapy until disease progression. Capecitabine was administered on days 14 through 52 (650 mg/m2 orally twice daily for the first six patients; 825 mg/m2 for the remaining patients).

RESULTS

Significant acute gastrointestinal (43% grade 2; 4% grade 3), hand and foot syndrome (21% grade 2), and transient hematologic (8% grade 3 or greater) events were uncommon with protocol mandated dose reductions of capecitabine grade 2 toxicity (43% of patients). Among the first 30 patients treated, three patients had tumor-associated bleeding duodenal ulcers, and one had a contained duodenal perforation. No additional bleeding events occurred among the final 18 patients after patients with duodenal involvement by tumor were excluded. Nine (20%) of 46 assessable patients had confirmed partial responses until distant progression for a median of 6.2 months. Four patients have undergone pancreaticoduodenectomy without perioperative complication. The median survival was 11.6 months (95% CI, 9.6 to 13.6), from the start of protocol therapy.

CONCLUSION

Concurrent bevacizumab did not significantly increase the acute toxicity of a relatively well-tolerated chemoradiotherapy regimen. However, ulceration and bleeding in the radiation field possibly related to bevacizumab occurred when tumor involved the duodenal mucosa. The encouraging efficacy end points suggest that the further study of bevacizumab with chemoradiotherapy is warranted.

Cytotoxic Chemotherapy for Pancreatic Cancer

Chemotherapy remains the mainstay of treatment for pancreatic cancer as most patients present with advanced disease, which precludes locoregional treatment. However, the efficacy of chemotherapy is limited. Gemcitabine is the only agent that improves symptoms and confers a modest survival advantage. Many combination therapy regimens have been studied in phase II settings. Eleven randomised phase III trials have been conducted to compare gemcitabine-containing regimens with gemcitabine monotherapy since gemcitabine became available clinically. The combination of gemcitabine plus capecitabine has demonstrated a survival advantage over gemcitabine, whereas gemcitabine plus oxaliplatin and gemcitabine plus cisplatin have shown improved progression-free survival or time to tumour progression but failed to demonstrate a survival advantage over gemcitabine. The search for effective therapy for advanced pancreatic cancer continues. Gemcitabine in combination with cytotoxic agents or molecular targeted agents hold promise.

Prostaglandin E2 drives cyclooxygenase-2 expression via cyclic AMP response element activation in human pancreatic cancer cells

Cyclooxygenase-2 (COX-2) is constitutively expressed in most human primary carcinomas and with its synthesized product, prostaglandin E2 (PGE2), appears to play important roles in tumor invasion, angiogenesis, resistance to apoptosis and suppression of host immunity. However, the molecular mechanisms that control COX-2 expression are unclear. The purpose of this study was to clarify the mechanism of basal and PGE2-mediated COX-2 expression in the highly metastatic L3.6pl human pancreatic cancer cell line. Using RNA interference to disrupt the expression of CREB and the NF-kappaB p65 subunit, we found that both are involved in maintaining basal COX-2 expression in L3.6pl cells. We also demonstrated that PGE2 increased the cyclic AMP concentration, thereby activating protein kinase A (PKA), which in turn phosphorylated the cyclic AMP response element binding protein (CREB), leading to interaction with the cyclic AMP response element in the promoter region of the COX-2 gene. Immunocytochemical analysis confirmed that PGE2 stimulated the translocation of PKA to the nucleus and increased the immuno-reactivity of phosphorylated CREB. Pretreatment with the PKA selective inhibitor H 89 and the E-prostanoid receptor 2 inhibitor AH 6809 reduced COX-2 upregulation by PGE2. Electrophoretic mobility shift assay and chromatin immunoprecipitation assay results further suggested a role for CREB in COX-2 transcriptional control. Understanding the pathways that control COX-2 expression may lead to a better understanding of its dysregulation in pancreatic carcinomas and facilitate the development of novel therapeutic approaches.

A phase I surrogate endpoint study of SU6668 in patients with solid tumors

PURPOSE

To evaluate the biologic effects of SU6668 in patients with solid tumors using comprehensive measures of pharmacokinetics (PK), functional imaging, and tissue correlative studies.

EXPERIMENTAL DESIGN

Eligible patients with tumors accessible for core needle biopsy were treated with SU6668 at doses of 200 or 400 mg/m(2)/day. Functional computed tomography (CT) scan and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) were performed at baseline and repeated 4 weeks and 12 weeks after treatment for analysis of tumor angiogenesis. The PK was analyzed using a high-performance liquid chromatography assay. Tumor specimens obtained via core needle biopsy at baseline and 4 weeks later were analyzed for the biologic effects of SU6668.

RESULTS

Six of a total of seven patients received treatment for at least 3 months and underwent comprehensive correlative studies, including PK, imaging, and tissue biopsy. Functional CT showed that five of six patients had decreased blood flow in tumors in response to treatment, and DCE-MRI results indicated significant change of area under the signal intensity vs. time curve (AUC) and/or maximum slope (maximum rate of signal intensity change) in two of four patients evaluated with this technique. PK studies showed that the mean apparent oral clearance (Cl(oral)) measured on day 1 was 6.3 +/- 2.7 L/hr/m(2), yielding a mean AUC of 16.6 +/- 4.3 mg/L.hr. By day 22, the Cl(oral) was 40% more than that observed on day 1.

CONCLUSION

It is feasible to evaluate the biologic effects of antiangiogenic agents using comprehensive surrogate measures.

Radiation Dose Considerations in the Palliative Treatment of Locally Advanced Adenocarcinoma of the Pancreas

Treatment of locally advanced pancreatic cancer with high-dose radiotherapy has not been curative, and can be difficult to tolerate. We decided to compare retrospectively the outcomes of patients treated concurrently with 5-fluorouracil and either 30 Gy or more than 30 Gy of radiation. From December 1993 through May 2001, 107 patients with locally advanced adenocarcinoma of the pancreas had been treated with palliative chemoradiation. Eighty-six patients had received a prescribed dose of 30 Gy and 50.4 Gy had been prescribed in 18 patients. Two of these patients were unable to complete the full dose of radiotherapy due to toxicity, and 3 received intraoperative radiotherapy boost (20 Gy). Three additional patients received a prescribed dose of 33 Gy, 36 Gy, and 52.2 Gy, respectively. These patients were grouped together (n = 21, median 50.4 Gy). All patients had received concurrent protracted venous infusions of 5-fluorouracil (300 mg/m Monday through Friday). The median survival time was not affected significantly by a higher radiotherapy dose (8 months for the 30 Gy group versus 9 months for the group receiving higher doses; P = 0.64). The 6-month actuarial progression rates were 45% versus 50% (P = 0.90) for local disease progression, and 54% versus 50% (P = 0.94) for distant metastasis for the 30 Gy and the higher dose groups, respectively. Ten of the 86 patients (12%) who had received 30 Gy were hospitalized for treatment-related gastrointestinal toxicity (grade 3) versus 6 of the 21 (29%) patients given higher doses (P = 0.05). Compared with higher doses given over 5 to 6 weeks, chemoradiation (30 Gy in 10 fractions in 2 weeks with concurrent infusional 5-FU) results in a similar median survival, and local disease progression rates in patients with locally advanced pancreatic cancer apparently do not substantially improve local disease control or median survival time. Because higher doses of radiotherapy can lead to increased acute treatment-related morbidity, we recommend using 30 Gy in 10 fractions unless the patient is part of a prospective study evaluating novel biologic or cytotoxic radiosensitizers.

A pharmacological study of celecoxib and gemcitabine in patients with advanced pancreatic cancer

PURPOSE

To evaluate whether celecoxib alters the conversion of gemcitabine into its active metabolite, difluorodeoxycytidine triphosphate (dFdCTP), in peripheral blood mononuclear cells (PBMCs).

METHODS

Patients with advanced pancreatic cancer who had not received chemotherapy and had acceptable organ function were eligible for the study. The initial dose of gemcitabine was 750 mg/m(2) administered intravenously at a rate of 10 mg/m(2)/min on days 1, 8, and 15 every 4 weeks. Celecoxib was administered orally at 400 mg twice a day starting 2 days after the first dose of gemcitabine. Serial blood samples were taken during the first and second gemcitabine infusions and the cellular dFdCTP levels from PBMCs were analyzed.

RESULTS

Five patients received gemcitabine at 750 mg/m(2) and six patients received it at 650 mg/m(2). Severe adverse events included neutropenia, thrombocytopenia, enteritis, and gastric perforation. Two patient died early during treatment. Cellular pharmacology studies showed that the conversion of gemcitabine into dFdCTP was not affected by celecoxib.

CONCLUSION

Despite the increased clinical toxicities encountered with the combination, celecoxib did not alter the conversion of gemcitabine into its active metabolites in PBMCs. Gemcitabine 650 mg/m(2) infusion over 65 min on days 1, 8, and 15 every 4 weeks in combination with celecoxib at 400 mg twice a day was the dose recommended for further study.

Pharmacodynamic analysis of target inhibition and endothelial cell death in tumors treated with the vascular endothelial growth factor receptor antagonists SU5416 or SU6668

PURPOSE

To determine the effects of small molecule inhibitors of vascular endothelial growth factor receptor (VEGFR)-2 (SU5416 and SU6668) on receptor phosphorylation in tumor xenografts and in paired tumor biopsies obtained in three clinical trials in patients with advanced solid malignancies.

EXPERIMENTAL DESIGN

The dose-dependent effects of SU6668 on angiogenesis and tumor growth were investigated in orthotopic L3.6pl pancreatic tumors. Excisional or 18G core biopsies were obtained from patients before and after therapy with SU5416 or SU6668. Laser scanning cytometry-mediated analysis was used to quantify levels of phosphorylated and total VEGFRs and platelet-derived growth factor receptors (PDGFR), tumor microvessel densities, vessel sizes, and endothelial and tumor cell apoptosis.

RESULTS

Significant inhibition of tumor microvessel density and growth and increased apoptosis were observed at SU6668 maximum tolerated dose (100 mg/kg) in L3.6pl xenografts. At 6 hours post therapy, SU6668 reduced VEGFR and PDGFR phosphorylation in the tumors by 50% and 92%, respectively, but levels rebounded beyond the baselines by 24 hours. Levels of phosphorylated VEGFR-2 and PDGFR also decreased significantly ( approximately 50%) 6 hours after therapy in 1 of 6 primary human tumors treated with SU6668, but these effects were not associated with increased apoptosis. A significant increase in endothelial cell apoptosis was observed in one tumor exposed to SU5416 and was associated with an increase in vessel size, but these changes occurred without an increase in tumor cell death.

CONCLUSIONS

SU5416 and SU6668 displayed biological activity in xenografts. However, neither drug produced marked biological activity in primary patient tumors.

Pharmacodynamic Analysis of Target Inhibition and Endothelial Cell Death in Tumors Treated with the Vascular Endothelial Growth Factor Receptor Antagonists SU5416 or SU6668

Purpose: To determine the effects of small molecule inhibitors of vascular endothelial growth factor receptor (VEGFR)-2 (SU5416 and SU6668) on receptor phosphorylation in tumor xenografts and in paired tumor biopsies obtained in three clinical trials in patients with advanced solid malignancies.

Experimental Design: The dose-dependent effects of SU6668 on angiogenesis and tumor growth were investigated in orthotopic L3.6pl pancreatic tumors. Excisional or 18G core biopsies were obtained from patients before and after therapy with SU5416 or SU6668. Laser scanning cytometry–mediated analysis was used to quantify levels of phosphorylated and total VEGFRs and platelet-derived growth factor receptors (PDGFR), tumor microvessel densities, vessel sizes, and endothelial and tumor cell apoptosis.

Results: Significant inhibition of tumor microvessel density and growth and increased apoptosis were observed at SU6668 maximum tolerated dose (100 mg/kg) in L3.6pl xenografts. At 6 hours post therapy, SU6668 reduced VEGFR and PDGFR phosphorylation in the tumors by 50% and 92%, respectively, but levels rebounded beyond the baselines by 24 hours. Levels of phosphorylated VEGFR-2 and PDGFR also decreased significantly (≈50%) 6 hours after therapy in 1 of 6 primary human tumors treated with SU6668, but these effects were not associated with increased apoptosis. A significant increase in endothelial cell apoptosis was observed in one tumor exposed to SU5416 and was associated with an increase in vessel size, but these changes occurred without an increase in tumor cell death.

Conclusions: SU5416 and SU6668 displayed biological activity in xenografts. However, neither drug produced marked biological activity in primary patient tumors.

Molecular targeting therapy for pancreatic cancer

Pancreatic carcinogenesis is driven by multiple genetic and epigenetic changes. The epidermal growth factor receptor (EGFR) and its downstream signaling pathways, Ras-Raf-MEK-ERK axis, play important roles in pancreatic cancer development. The phosphoinositol 3 kinase (PI3 K)/Akt and the nuclear factor kappaB (NF-kappaB) pathways control both proliferation and resistance to apoptosis of pancreatic cancer. The role of cyclooxygenase (COX) and lipoxygenase (LOX) in the development of pancreatic cancer has been made known recently. The elucidation of these molecular events has led to several distinct therapeutic advances, including therapies that target EGFR, the Ras-Raf-MEK-ERK axis, the COX-2 and LOX pathways, and others. Many novel agents have been developed and are undergoing clinical investigation, such as monoclonal antibodies against EGFR, tyrosine kinase inhibitors (TKIs), farnesyl transferase inhibitors (FTIs), Bay43-9006, CI-1040, CCI-779, celecoxib, and LY293111. This review highlights recent advances in the development of these agents.

Adjuvant therapy for pancreatic cancer: current status and future directions

This article summarizes the important past and ongoing adjuvant therapy trials for pancreatic cancer. The recent developments in the fields of radiosensitization, chemotherapy, and molecular-targeted therapy are outlined. Finally, the future study strategies for adjuvant therapy trials are discussed.

Cetuximab, a monoclonal antibody targeting the epidermal growth factor receptor, in combination with gemcitabine for advanced pancreatic cancer: a multicenter phase II Trial

PURPOSE

To determine the response rate, time to disease progression, survival duration and rate, and toxicity with the combination of cetuximab and gemcitabine in patients with epidermal growth factor receptor (EGFR)-expressing advanced pancreatic cancer.

PATIENTS AND METHODS

Patients with measurable locally advanced or metastatic pancreatic cancer who had never received chemotherapy for their advanced disease and had immunohistochemical evidence of EGFR expression were eligible for the multicenter phase II trial. Patients were treated with cetuximab at an initial dose of 400 mg/m(2), followed by 250 mg/m(2) weekly for 7 weeks. Gemcitabine was administered at 1,000 mg/m(2) for 7 weeks, followed by 1 week of rest. In subsequent cycles, cetuximab was administered weekly, and gemcitabine was administered weekly for 3 weeks every 4 weeks.

RESULTS

Sixty-one patients were screened for EGFR expression, 58 patients (95%) had at least 1+ staining, and 41 were enrolled onto the trial. Five patients (12.2%) achieved a partial response, and 26 (63.4%) had stable disease. The median time to disease progression was 3.8 months, and the median overall survival duration was 7.1 months. One-year progression-free survival and overall survival rates were 12% and 31.7%, respectively. The most frequently reported grade 3 or 4 adverse events were neutropenia (39.0%), asthenia (22.0%), abdominal pain (22.0%), and thrombocytopenia (17.1%).

CONCLUSION

Cetuximab in combination with gemcitabine showed promising activity against advanced pancreatic cancer. Further clinical investigation is warranted.

Novel therapies for pancreatic adenocarcinoma

Despite advances in our understanding of the molecular and genetic basis of pancreatic cancer, the disease remains a clinical challenge. Gemcitabine, the standard chemotherapy for pancreatic cancer, offers modest improvement of tumor-related symptoms and marginal advantage of survival. New approaches, alone and in combination with gemcitabine, are being developed to combat this cancer. In this article we review the current status of investigations into several classes of agents: matrix metalloproteinase inhibitors; farnesyl transferase inhibitors; epidermal growth factor receptor inhibitors, including monoclonal antibodies and tyrosine kinase inhibitors; cyclooxygenase-2 inhibitors, and others. The scientific rationale, mechanism of action, and clinical trial data for these novel agents are discussed.

Celecoxib inhibits vascular endothelial growth factor expression in and reduces angiogenesis and metastasis of human pancreatic cancer via suppression of Sp1 transcription factor activity

The aggressive biology of human pancreatic adenocarcinoma has been linked with overexpression of vascular endothelial growth factor (VEGF). Constitutive activation of the transcription factor Sp1 plays a critical role in VEGF overexpression. Recent studies indicated that celecoxib, a selective cyclooxygenase-2 inhibitor, exhibits potent antitumor activity. However, the underlying molecular mechanisms of this activity remain unclear. In the present study, we used a pancreatic cancer model to determine the role of Sp1 in the antitumor activity of celecoxib. Treatment of various pancreatic cancer cells with celecoxib suppressed VEGF expression at both the mRNA and protein level in a dose-dependent manner. VEGF promoter deletion and point mutation analyses indicated that a region between nucleotide -109 and -61 and its intact Sp1-binding sites were required for the inhibition of VEGF promoter activity by celecoxib. Also, celecoxib treatment reduced both Sp1 DNA binding activity and transactivating activity. This decreased activity correlated with reduced Sp1 protein and its phosphorylation as determined using Western blot analysis. Furthermore, in an orthotopic pancreatic cancer animal model, celecoxib treatment inhibited tumor growth and metastasis. The antitumor activity was consistent with inhibition of angiogenesis as determined by evaluating tumor microvessel formation, which correlated with decreased Sp1 activity and VEGF expression. Collectively, our data provide a novel molecular mechanism for the antitumor activity of celecoxib and may help further improve its effectiveness in controlling pancreatic cancer growth and metastasis.

Experimental animal models of pancreatic carcinogenesis and metastasis

Pancreatic cancer is a lethal disease characterized by early metastasis, local invasion, and resistance to conventional therapies. To understand its etiology and eventually make prevention of it possible and effective, appropriate carcinogenesis models will certainly help us understand the effects of environmental and genetic elements on pancreatic carcinogenesis. The development of new treatment strategies to control cancer metastasis is of immediate urgency. Fulfillment of this task relies on our knowledge of the cellular and molecular biology of pancreatic cancer metastasis and the availability of biologically and clinically relevant model systems. Many of the existing pancreatic cancer carcinogenesis and metastasis animal models are described in this review. The advantages and disadvantages of each model and their clinical implications are discussed, and special attention is focused on experimental therapeutic strategies targeting pancreatic cancer metastasis.

NF-kappaB activity blockade impairs the angiogenic potential of human pancreatic cancer cells

The effect of blockade of NF-kappaB activity on human pancreatic cancer angiogenesis was determined in an orthotopic xenograft model. Highly metastatic L3.3 human pancreatic cancer cells, which expressed an elevated level of constitutive NF-kappaB activity, were transfected with a mutated IkappaBalpha (IkappaBalphaM). After implantation in the pancreas of nude mice, parental (L3.3) and control vector-transfected (L3.3-Neo) cells produced rapidly growing tumors and liver metastases, whereas IkappaBalphaM-transfected (L3.3-IkappaBalphaM) cells had decreased tumorigenicity and metastatic potential. NF-kappaB signaling blockade significantly inhibited the in vitro and in vivo expression of the major proangiogenic molecules vascular endothelial growth factor and interleukin-8 and decreased tumor vascular formation. These events were correlated with retarded tumor growth and suppression of metastasis. Collectively, these data suggest that suppression of tumorigenicity and metastasis by NF-kappaB blockade is due to impaired angiogenic potential of tumor cells.

Treatment of colorectal cancer metastasis: The role of chemotherapy

5-Fluorouracil (5-FU) has been the main chemotherapeutic agent for the treatment of colorectal cancer for four decades with modest efficacy. Modulation of 5-FU by leucovorin or continuous infusion improves the response rate, but overall survival duration remains approximately 12 months. Many oral fluoropyrimidines have been studied, including capecitabine, UFT, S-1, and Eniluracil. Capecitabine has demonstrated equivalent efficacy with 5-FU and has been approved as first line treatment. The combinations of capecitabine with CPT-11 or oxaliplatin are being developed. CPT-11 demonstrated non-crossover resistance with 5-FU and was proven to be effective treatment for patients who received prior 5-FU. CPT-11 in combination with 5-FU has demonstrated improved response rate and overall survival duration over 5-FU or CPT-11. Oxaliplatin plus 5-FU has offered another effective treatment option for colorectal cancer. Both 5-FU plus leucovorin in combination with CPT-11 or oxaliplatin are widely used first-line chemotherapies for advanced colorectal cancer. Optimal combinations and sequences of treatment are being studied, since several effective regimens have become available.

Chemoradiation for resectable gastric cancer

The incidence of gastric cancer has been declining in recent years, however, the disease continues to be a worldwide public health problem. About two thirds of patients with gastric cancer undergo surgical resection with curative intent. R0 resection--complete local-regional tumour removal with negative resection margins--is the only curative modality. The optimum extent of lymph-node dissection (D1 vs D2) is controversial. Disease relapse, both local and distant, is common and the 5-year survival rate is disappointing. Adjuvant chemotherapy has been studied extensively in this setting but an effective regimen has not yet been identified. A recent intergroup study has shown that postoperative chemoradiation is effective in improving both disease-free survival (3-year, 48% vs 31%, p<0.001) and overall survival (3-year, 50% vs 41%, p=0.005) compared with surgery alone. Preoperative radiation as a single adjuvant therapy has also yielded improvements in local-regional control, disease-free survival, and overall survival compared with surgery alone. Preoperative chemotherapy or chemoradiation has been accepted to have a theoretical advantage over postoperative therapy and has now been shown to be a feasible option. Its efficacy, however, remains to be tested.

Phase I and pharmacological study of oral 9-aminocamptothecin colloidal dispersion (NSC 603071) in patients with advanced solid tumors

PURPOSE

9-Aminocamptothecin colloidal dispersion (9-ACCD; NSC 603071) is a specific inhibitor of topoisomerase I that can be given p.o. This Phase I trial was conducted to determine the toxicity profile, maximal tolerated dose, and pharmacokinetics profile, including bioavailability, of p.o. 9-ACCD in patients with advanced solid tumors.

EXPERIMENTAL DESIGN

After receiving one i.v. dose of 9-ACCD, patients were treated with 9-ACCD p.o., starting with a 2-week schedule, to establish the safety. Once safety was established, patients were treated continuously for 4 weeks followed by a rest period of 2 weeks at dosages of 0.2, 0.3, 0.45, 0.56, 0.7, and 0.63 mg/m(2)/day. Serial blood samples were collected for the pharmacokinetics study on day 1 after the i.v. dose and day 2 after p.o. administration. Lactone and total 9-aminocamptothecin were analyzed by high-pressure liquid chromatographic assay.

RESULTS

Thirty-two patients were treated on the study. The dose-limiting toxicity was myelosuppression at the dosage of 0.7 mg/m(2)/day. Other toxic effects included nausea, vomiting, fatigue, and transient elevation of the total bilirubin level. The maximal tolerated dose was 0.63 mg/m(2)/day. There was no objective response. The mean terminal half-life of p.o. total 9-ACCD was 1.2 +/- 1.2 h, and the volume of distribution was 17.7 +/- 20.6 l/m(2). The mean bioavailability of total 9-ACCD was 68.1 +/- 36.4%.

CONCLUSIONS

Despite good tolerance of p.o. administration, the lack of clinical activity and variable absorption of 9-ACCD suggested that further development might not be warranted.

Stat3 activation regulates the expression of vascular endothelial growth factor and human pancreatic cancer angiogenesis and metastasis

Expression of vascular endothelial growth factor (VEGF), a key angiogenic protein, has been linked with pancreatic cancer progression. However, the molecular basis for VEGF overexpression remains unclear. Immunohistochemical studies have indicated that VEGF overexpression coincides with elevated Stat3 activation in human pancreatic cancer specimens. In our study, more than 80% of the human pancreatic cancer cell lines used exhibited constitutively activated Stat3, with Stat3 activation correlated with the VEGF expression level. Blockade of activated Stat3 via ectopic expression of dominant-negative Stat3 significantly suppressed VEGF expression, angiogenesis, tumor growth, and metastasis in vivo. Furthermore, constitutively activated Stat3 directly activated the VEGF promoter, whereas dominant-negative Stat3 inhibited the VEGF promoter. A putative Stat3-responsive element on the VEGF promoter was identified using a protein-DNA binding assay and confirmed using a promoter mutagenesis assay. These results indicate that Stat3 directly regulates VEGF expression and hence angiogenesis, growth, and metastasis of human pancreatic cancer, suggesting that Stat3 signaling may be targeted for treatment of pancreatic cancer.

Epidermal growth factor receptor-targeted therapy for pancreatic cancer

Epidermal growth factor receptor (EGFR) plays an important role in tumor development and maintenance. It is a cell surface molecule that mediates signal transduction from the cell surface to cytoplasm. Elevated expression of EGFR or its ligand correlates with worse prognosis in a variety of human cancers. Therefore, blockade of EGFR activity would provide a novel strategy for the treatment of cancer. Two classes of EGFR inhibitors, monoclonal antibodies and tyrosine kinase inhibitors, have been described. The preclinical activity of these EGFR inhibitors and phase I clinical data are summarized in this article. A phase II trial of the EGFR inhibitor IMC-C225 in combination with gemcitabine for patients with advanced pancreatic cancer is discussed.