Phase II trial of weekly docetaxel/irinotecan combination in advanced pancreatic cancer

Clinical and Pre-Clinical Evidence of Carbonic Anhydrase IX in Pancreatic Cancer and Its High Expression in Pre-Cancerous Lesions

Hypoxia is a common phenomenon that occurs in most solid tumors. Regardless of tumor origin, the evolution of a hypoxia-adapted phenotype is critical for invasive cancer development. Pancreatic ductal adenocarcinoma is also characterized by hypoxia, desmoplasia, and the presence of necrosis, predicting poor outcome. Carbonic anhydrase IX (CAIX) is one of the most strict hypoxia regulated genes which plays a key role in the adaptation of cancer cells to hypoxia and acidosis. Here, we summarize clinical data showing that CAIX expression is associated with tumor necrosis, vascularization, expression of Frizzled-1, mucins, or proteins involved in glycolysis, and inevitably, poor prognosis of pancreatic cancer patients. We also describe the transcriptional regulation of CAIX in relation to signaling pathways activated in pancreatic cancers. A large part deals with the preclinical evidence supporting the relevance of CAIX in processes leading to the aggressive behavior of pancreatic tumors. Furthermore, we focus on CAIX occurrence in pre-cancerous lesions, and for the first time, we describe CAIX expression within intraductal papillary mucinous neoplasia. Our review concludes with a detailed account of clinical trials implicating that treatment consisting of conventionally used therapies combined with CAIX targeting could result in an improved anti-cancer response in pancreatic cancer patients.

A Pilot Trial of Molecularly Tailored Therapy for Patients with Metastatic Pancreatic Ductal Adenocarcinoma

Purpose: Despite the wide adoption of tumor molecular profiling, there is a dearth of evidence linking molecular biomarkers for treatment selection to prediction of treatment outcomes in patients with metastatic pancreatic cancer. We initiated a pilot study to test the feasibility of designing a larger phase II trial of molecularly tailored treatment for metastatic pancreatic cancer.

Methods: Our study aimed to assess the feasibility of following a treatment algorithm based on the expression of three published predictive markers of response to chemotherapy: ribonucleotide reductase catalytic subunit M1 (for gemcitabine); excision repair cross-complementation group 1 (for platinum agents); and thymidylate synthase (for 5-fluorouracil) in patients with untreated, metastatic pancreatic cancer. Results of the tumor biopsy analysis were used to assign patients to one of seven doublet regimens. Key secondary objectives included response rate (RR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS).

Results: Between December 2012 and March 2015, 30 patients were enrolled into the study. Ten patients failed screening primarily due to inadequate tumor tissue availability. Of the remaining 20 patients, 19 were assigned into 6 different chemotherapy doublets, and achieved an RR of 28%, with a DCR rate of 78%. The median PFS and OS were 5.78 and 8.21 months, respectively.

Conclusions: The incorporation of biomarkers into a treatment algorithm is feasible and resulted in a PFS and OS similar to other doublet therapies for patients with metastatic pancreatic cancer. Based on the results from this pilot study, a larger phase II randomized trial of molecularly targeted therapy versus physicians' choice of standard of care has been initiated in the second-line setting (NCT02967770).

Scalable Multiplexed Drug-Combination Screening Platforms Using 3D Microtumor Model for Precision Medicine

Cancer heterogeneity is a notorious hallmark of this disease, and it is desirable to tailor effective treatments for each individual patient. Drug combinations have been widely accepted in cancer treatment for better therapeutic efficacy as compared to a single compound. However, experimental complexity and cost grow exponentially with more target compounds under investigation. The primary challenge remains to efficiently perform a large-scale drug combination screening using a small number of patient primary samples for testing. Here, a scalable, easy-to-use, high-throughput drug combination screening scheme is reported, which has the potential of screening all possible pairwise drug combinations for arbitrary number of drugs with multiple logarithmic mixing ratios. A "Christmas tree mixer" structure is introduced to generate a logarithmic concentration mixing ratio between drug pairs, providing a large drug concentration range for screening. A three-layer structure design and special inlets arrangement facilitate simple drug loading process. As a proof of concept, an 8-drug combination chip is implemented, which is capable of screening 172 different treatment conditions over 1032 3D cancer spheroids on a single chip. Using both cancer cell lines and patient-derived cancer cells, effective drug combination screening is demonstrated for precision medicine.

Randomized Phase II Trial of Irinotecan/Docetaxel or Irinotecan/Docetaxel Plus Cetuximab for Metastatic Pancreatic Cancer: An Eastern Cooperative Oncology Group Study

Objectives:

The primary objective was to determine the response rate in patients with metastatic pancreatic cancer treated in first line with irinotecan/docetaxel combination (Arm A) or with irinotecan/docetaxel/cetuximab combination (Arm B). Secondary endpoints were progression-free survival (PFS), overall survival (OS), toxicity, and the rate of thromboembolic events with prophylactic enoxaparin sodium.

Patients and Methods:

Patients were eligible who had measurable, metastatic adenocarcinoma of the pancreas, and normal bilirubin. All patients received anticoagulation. Docetaxel (35 mg/m²) and irinotecan (50 mg/m²) were administered once a week for 4 weeks followed by 2 weeks rest (Arm A) alone or with the addition of cetuximab (Arm B). The primary endpoint was response rate.

Results:

A total of 87 eligible patients were enrolled and treated. Grade 3/4 toxicity was observed in 74% of patients in Arm A and 76% in Arm B. The principal grade 3/4 toxicity was diarrhea. Response rates were 4.5% in Arm A and 7% in Arm B. Median PFS and OS were 3.9 and 6.5 months in Arm A and 4.5 and 5.4 months in Arm B.

Conclusions:

Docetaxel/irinotecan combination is associated with considerable toxicity. Objective responses were infrequent and addition of cetuximab in an unselected population was not beneficial, but PFS and OS were comparable with those achieved with other regimens. Docetaxel/irinotecan therapy is active in metastatic pancreatic cancer.

Irinophore C™, a lipid nanoparticle formulation of irinotecan, abrogates the gastrointestinal effects of irinotecan in a rat model of clinical toxicities

Irinotecan is a water-soluble camptothecin derivative with clinical activity against colorectal and small cell lung cancers and is currently a standard of care therapeutic in the treatment of colorectal cancer in combination with 5-fluorouracil. One of the major clinical issues limiting the use of irinotecan is gastrointestinal toxicity manifested as life-threatening diarrhea which is reported in up to 45 % of treated patients. The studies summarized here tested, in a rat model of irinotecan-associated gastro-intestinal toxicity, whether a lipid nanoparticle formulation of irinotecan, Irinophore C™, mitigated early-onset or late-onset diarrhea when given at doses equivalent to unformulated irinotecan that engenders both early- and late-onset diarrhea. Specifically, rats administered intravenously on two consecutive days with unformulated irinotecan at 170 mg/kg then 160 mg/kg experienced transient early-onset diarrhea after each administration and then experienced significant late-onset diarrhea peaking 4 days after treatment. Irinophore C™ given at the identical dose and schedule did not elicit either early- or late-onset diarrhea in any animals. When Irinophore C™ was combined with 5-fluorouracil there was also no early- or late-onset diarrhea observed. Histopathological analysis of the gastro-intestinal tract confirmed that the effects associated with irinotecan treatment were absent in rats given Irinophore C™ at the identical dose. Pharmacokinetic analysis demonstrated significantly higher systemic concentrations of irinotecan in rats given the nanoparticle formulation compared to those given unformulated irinotecan. These results demonstrate that the Irinophore C™ formulation is significantly less toxic than irinotecan, used either as a single agent or in combination with 5-fluorouracil, in a rat model of irinotecan-induced gastrointestinal toxicity.

Tumor-specific targeting of pancreatic cancer with Shiga toxin B-subunit

Pancreatic carcinoma is one of the most aggressive tumor entities, and standard chemotherapy provides only modest benefit. Therefore, specific targeting of pancreatic cancer for early diagnosis and therapeutic intervention is of great interest. We have previously shown that the cellular receptor for Shiga toxin B (STxB), the glycosphingolipid globotriaosylceramide (Gb(3) or CD77) is strongly increased in colorectal adenocarcinoma and their metastases. Here, we report an upregulation of Gb(3) in pancreatic adenocarcinoma (21 of 27 cases) as compared with matched normal tissue (n = 27). The mean expression was highly significantly increased from 30 ± 16 ng Gb(3)/mg tissue in normal pancreas to 61 ± 41 ng Gb(3)/mg tissue (mean ± SD, P = 0.0006), as evidenced by thin layer chromatography. Upregulation of Gb(3) levels did not depend on tumor stage or grading and showed no correlation with clinical outcome. Tumor cells and endothelial cells were identified as the source of increased Gb(3) expression by immunocytochemistry. Pancreatic cancer cell lines showed rapid intracellular uptake of STxB to the Golgi apparatus, following the retrograde pathway. The therapeutic application of STxB was tested by specific delivery of covalently coupled SN38, an active metabolite of the topoisomerase I inhibitor irinotecan. The cytotoxic effect of the STxB-SN38 compound in pancreatic cancer cell lines was increased more than 100-fold compared with irinotecan. Moreover, this effect was effectively blocked by competing incubation with nonlabeled STxB, showing the specificity of the targeting. Thus, STxB constitutes a promising new tool for specific targeting of pancreatic cancer.

Contribution of thymidylate synthase to gemcitabine therapy for advanced pancreatic cancer

OBJECTIVES

Thymidylate synthase (TS) inhibitors activate human equilibrative nucleoside transporter 1. We evaluated the contribution of TS expression to determine a treatment method providing an effect from gemcitabine (GEM).

METHODS

The expression of 5-fluorouracil (5-FU) and GEM metabolic factors (5-FU: TS, dihydropyrimidine dehydrogenase, orotate phosphoribosyltransferase; GEM: human equilibrative nucleoside transporter 1, deoxycytidine kinase, cytidine deaminase, 5'-nucleotidase) were studied in 7 pancreatic cancer cell lines by Western blotting, and drug resistance was evaluated by 3-[4,5-dimethylthiazol]-2,5-dephenyl tetrazolium bromide assay. The expression of 5-FU factors was observed immunohistochemically in resected pancreatic cancer specimens.

RESULTS

Gemcitabine concentrations that inhibited colony formation by 50% correlated with TS protein expression (P = 0.0169). With a 5-FU non-growth-inhibiting dose, GEM concentrations that inhibited colony formation by 50% were significantly reduced by one fourth to one tenth. Knockout of TS expression by small interfering RNA decreased resistance to GEM in the cell lines (P = 0.0019). Immunohistochemically, TS expression related to disease-free survival time of patients treated with GEM (P = 0.0224). A high expression of 5-FU factors was detected: orotate phosphoribosyltransferase: differentiated cases (P = 0.0137), lower T factor (P = 0.0411); dihydropyrimidine dehydrogenase: nerve invasion (P = 0.0188), lymph node recurrence (P = 0.0253); TS, positive N factor (P = 0.0061).

CONCLUSIONS

The expression of TS provides an alternative source of substrate for DNA synthesis and positively correlates with GEM resistance and shortened patient survival.

Docetaxel and irinotecan in recurrent or metastatic head and neck cancer: a phase 2 trial of the Eastern Cooperative Oncology Group

BACKGROUND

Docetaxel and irinotecan have single-agent antitumor activity in squamous cell carcinoma of the head and neck (SCCHN). The authors sought to evaluate their combination in the treatment of patients with recurrent or metastatic SCCHN.

METHODS

Eligibility criteria included recurrent or metastatic SCCHN with measurable disease, good performance status, and adequate laboratory parameters. Patients received docetaxel 35 mg/m(2) and irinotecan 60 mg/m(2), intravenously, on Days 1 and 8, every 21 days, until disease progression. The authors assessed UGT1A1 genotype, vascular endothelial growth factor (VEGF) in serum, and cyclooxygenase-2 and VEGF in baseline tumor tissue.

RESULTS

Fifty-two patients were analyzable: 20 chemotherapy naive (Group A) and 32 previously treated with 1 chemotherapy regimen (Group B); 73% of patients had distant metastasis, and 60% were paclitaxel-exposed. In Group A, 3 (15%) patients achieved a partial response; in Group B, 1 (3%) patient achieved a partial response. Median progression-free survival (PFS) and overall survival were 3.3 and 8.2 months in Group A and 1.9 and 5.0 months in Group B, respectively. Common serious toxicities were diarrhea, fatigue, and anorexia. Patients with high serum VEGF had a median PFS of 2.8 months versus 1.7 months for patients with low VEGF (P = .085).

CONCLUSIONS

Docetaxel and irinotecan had acceptable toxicities, but efficacy results in unselected patients with recurrent or metastatic SCCHN did not suggest an advantage over docetaxel alone or platinum-based regimens.

The flavonoid apigenin potentiates the growth inhibitory effects of gemcitabine and abrogates gemcitabine resistance in human pancreatic cancer cells

OBJECTIVES

The aim of the study was to evaluate the effect of combination therapy of apigenin and gemcitabine on cell proliferation, the cell cycle, and gemcitabine resistance in human pancreatic cancer cells.

METHODS

Cell counting was used to assess the effect of single-agent and combination treatment on the proliferation of CD18 and AsPC-1 pancreatic cancer cells. Flow cytometry was performed to assess the effect of combination treatment on cell cycle progression and induction of apoptosis. Western blot analysis was used to evaluate phosporylated AKT (pAkt) and cell cycle proteins. The effect of apigenin on gemcitabine-resistant AsPC-1 cells was assessed via thymidine incorporation.

RESULTS

Apigenin in combination with gemcitabine inhibited pancreatic cancer cell proliferation more than either agent alone. Combination treatment induced both S and G2/M phase arrest and increased apoptosis. Apigenin down-regulated pAkt expression and abrogated gemcitabine-mediated pAkt induction. In gemcitabine-resistant AsPC-1 cells, apigenin significantly inhibited cell proliferation in a dose-dependent manner.

CONCLUSION

Combination treatment with apigenin and gemcitabine inhibited pancreatic cancer cell growth via cell cycle arrest, down-regulation of the prosurvival factor pAkt, and induction of apoptosis. Combination therapy may prove useful for the treatment of pancreatic cancer.

A phase I/II trial of fixed-dose docetaxel plus irinotecan and escalating doses of estramustine phosphate for second-line or greater treatment of selected advanced solid tumors

This phase I/II study evaluated the safety of the combination of irinotecan, docetaxel, and estramustine for selected advanced solid tumors and also obtained initial efficacy data. Twenty-two patients were enrolled in the study. The regimen consisted of docetaxel 30 mg/m(2) and irinotecan 60 mg/m(2) both given intravenously on days 1 and 8 every 21 days in combination with escalating doses of estramustine (500 mg/m(2)/day escalated to 750 mg/m(2)/day on days 0, 1, 2, 7, 8, and 9 given every 21 days) during phase I. Dose escalation was continued until the maximum planned dose level of estramustine (750 mg/m(2)/day) was reached. After the appropriate phase II dose of estramustine was found additional patients were enrolled. Twenty-one of the 22 patients were evaluable for toxicity and 17 for tumor response. The recommended phase II dose of estramustine was found to be 750 mg/m(2)/day orally on days 0, 1, 2, 7, 8, and 9 given every 21 days. Hematologic toxicity was fairly mild, with only one episode of grade 3 neutropenia. Diarrhea was the most common nonhematologic toxicity with grade 3 toxicity occurring in five of 21 patients. Only one episode of venous thrombosis was observed. Objective response rate was 15.8%, overall clinical benefit rate was 63%, and median time to progression was 15 weeks. Estramustine in combination with the doublet of docetaxel and irinotecan is a well-tolerated regimen with minimal hematologic toxicity, mild to moderate nonhematologic toxicity, and promising initial antitumor activity in previously treated patients with advanced solid tumors.

An explorative randomised phase II study of sequential chemotherapy in advanced upper gastrointestinal cancer

The feasibility, safety, and efficacy of planned sequential administration of docetaxel and irinotecan with 5-fluorouracil (5-FU)/leucovorin in advanced upper gastrointestinal adenocarcinoma (UGIA) are unknown. Seventy-three patients with gastric (GC; n = 22), pancreatic (PC; n = 28) or biliary cancer (BC; n = 23) were randomised to start with 45 mg/m(2) docetaxel or 180 mg/m(2) irinotecan combined with 5-FU/leucovorin every 2nd week. After every 2nd course, the patients were crossed over to the other combination. Treatment was given for a maximum of 12 courses. Quality-of-life (QoL) was evaluated during the first two months using the EORTC QLQ-C30. Eighteen patients (25%; GC 32%, PC 21%, BC 22%) demonstrated partial response (PR) and 21 (29%) had prolonged stable disease. Mean QoL scores were low at baseline. Twenty-three (32%) patients had improved QoL using a summary measure and 13 were stable. Median time to progression was 4.4 months and overall survival 8.2 months. The treatments were reasonably well tolerated. Grade 3-4 toxicities were slightly more common for the docetaxel combination. There were two treatment-related deaths. Planned sequential treatment with docetaxel or irinotecan with 5-FU/leucovorin is feasible, reasonably tolerable and appears active in advanced UGIA.