Preclinical Evaluation of ZD1839 Alone or in Combination with Oxaliplatin in a Panel of Human Tumor Cell Lines – Implications for Clinical Use

Suppression of proliferation of two independent NF1 malignant peripheral nerve sheath tumor cell lines by the pan-ErbB inhibitor CI-1033

Neurofibromatosis Type 1 (NF1) is characterized by the abnormal proliferation of neuroectodermal tissues and the development of certain tumors, particularly neurofibromas, which may progress into malignant peripheral nerve sheath tumors (MPNSTs). Effective pharmacological therapy for the treatment of NF1 tumors is currently unavailable and the prognosis for patients with MPNSTs is poor. Loss of neurofibromin correlates with increased expression of the epidermal growth factor receptor (EGFR) and ErbB2 tyrosine kinases and these kinases have been shown to promote NF1 tumor-associated pathologies in vivo. We show here that while NF1 MPNST cells have higher EGFR expression levels and are more sensitive to EGF when compared to a non-NF1 MPNST cell line, the ability of the EGFR inhibitor gefitinib to selectively inhibit NF1 MPNST cell proliferation is marginal. We also show that NF1 MPNST proliferation correlates with activated ErbB2 and can be suppressed by nanomolar concentrations of the pan-ErbB inhibitor CI-1033 (canertinib). Consequently, targeting both EGFR and ErbB2 may prove an effective strategy for suppressing NF1 MPNST tumor growth in vivo.

Gefitinib in combination with oxaliplatin and 5-fluorouracil in irinotecan-refractory patients with colorectal cancer: a phase I study of the Arbeits gemeinschaft Internistische Onkologie (AIO)

BACKGROUND

The aim of the study was to establish the recommended dose and to evaluate the safety of gefitinib plus FUFOX regimen in irinotecan-refractory colorectal carcinoma (CRC).

PATIENTS AND METHODS

Patients with advanced CRC progressing on fluoropyrimidine/irinotecan-based chemotherapy and with an ECOG performance level 0-2 were enrolled. Four dose levels with sequential dose escalation of oral gefitinib and FUFOX were tested. Each cycle consisted of 5 weeks with gefitinib given daily to weekly FUFOX x4 to be repeated at day 36.

RESULTS

Eighteen patients were enrolled. No dose-limiting toxicity (DLT) was observed at the dose levels L1-L3. At L4 diarrhea was the major DLT requiring treatment interruption in 3 patients. Other grade 3/4 toxicities were observed with skin rash, paresthesia, anemia, and nausea/vomiting (n = 1 each). Grade 1/2 toxicities consisted of diarrhea (n = 9), mucositis (8), skin rash (10), paresthesia (10), nausea (7) as well as leukopenia (2) and fever (1). Clinical benefit was seen in 11 of 16 evaluable patients (69%): 4 patients showed partial response (25%), 7 stable disease (44%). Median time to progression was 219 days (range 50-387 days).

CONCLUSION

Gefitinib at a dose of 250 mg daily in combination with weekly 5-fluorouracil at 2,000 mg/m(2) or gefitinib at a dose of 500 mg daily with 5-fluorouracil at 1,600 mg/m(2) plus oxaliplatin has an acceptable safety profile.

The Potential of Bioartificial Tissues in Oncology Research and Treatment

This review article addresses the relevance and potential of bioartificial tissues in oncologic research and therapy and reconstructive oncologic surgery. In order to translate the findings from basic cellular research into clinical applications, cell-based models need to recapitulate both the 3D organization and multicellular complexity of an organ but at the same time accommodate systematic experimental intervention. Here, tissue engineering, the generation of human tissues and organs in vitro, provides new perspectives for basic and applied research by offering 3D tissue cultures resolving fundamental obstacles encountered in currently applied 2D and 3D cell culture systems. Tissue engineering has already been applied to create replacement structures for reconstructive surgery. Applied in vitro, these complex multicellular 3D tissue cultures mimic the microenvironment of human tissues. In contrast to the currently available cell culture systems providing only limited insight into the complex interactions in tissue differentiation, carcinogenesis, angiogenesis and the stromal reaction, the more realistic (micro)environment afforded by the bioartificial tissuespecific 3D test systems may accelerate the progress in design and development of cancer therapies.

Epidermal growth factor receptor tyrosine kinase inhibitors: present and future role in gastrointestinal cancer treatment: a review

BACKGROUND

Despite advances in conventional and targeted anticancer therapy, the prognosis remains poor for many patients with solid tumors. Ongoing research into the molecular basis of malignant disease, however, has yielded many novel agents with potential activity, including the epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs).

DESIGN

This review summarizes current clinical data for EGFR-TKIs as monotherapy or in combination with 5-fluorouracil/leucovorin, irinotecan, or oxaliplatin, focusing on the rapidly developing area of colorectal, gastroesophageal, and pancreatic cancers.

RESULTS

EGFR-TKIs have limited but valuable activity as monotherapy in non-small cell lung cancer patients who have received prior anticancer treatment. The potential for application as a single agent in colorectal, gastroesophageal, and pancreatic cancers has yet to be demonstrated conclusively and deserves further investigation, especially as second- or third-line therapy. In combination with oxaliplatin-based regimens and 5-fluorouracil/leucovorin-based regimens, TKIs have shown benefits, suggesting that there may be a synergistic effect with chemotherapy. However, combinations with irinotecan-based regimens have been limited by toxicities.

CONCLUSIONS

EGFR-TKIs show benefits when used in combination with chemotherapy, and the favorable toxicity profiles observed suggest that these may be of value in frail or elderly patients.