XRP6258-induced gene expression patterns in head and neck cancer carcinoma

OBJECTIVES/HYPOTHESIS

XRP6258 is a novel taxoid, which has antitumor activity in preclinical mouse orthotopic and human xenograft cancer models. However, limited XRP6258 studies have been performed in head and neck squamous cell carcinoma cells (HNSCC). The objective of this study is to identify the antitumor activity of XRP6258 in HNSCC cell line models.

METHODS

HNSCC cells (HN30 and HN12) were exposed to either XRP6258 or docetaxel. XRP6258-induced growth suppression, cell cycle arrest and apoptosis were measured. Further, XRP6258-induced expression patterns of selected genes were compared to docetaxel-induced expression patterns using Western blot analysis.

RESULTS

XRP6258 suppressed proliferation and induced G(2)M arrest and apoptosis in both of the cell lines tested. XRP6258 and docetaxel produced similar alteration in the expression of cell cycle regulators, such as cyclin A and cyclin B1. The expression of E2F and EGFR were decreased in both XRP6258 and docetaxel-treated HNSCC cells. Finally, XRP6258 induced a greater level of bcl2 phosphorylation than docetaxel in HN12 cell line.

CONCLUSIONS

XRP6258 appeared to have a similar mechanism of action as docetaxel in the two HNSCC cell lines studied. XRP6258 induced cell cycle arrest, growth suppression, and apoptosis by altering gene expression patterns similar to that induced by docetaxel. These preclinical experiments suggest that XRP6258 may be useful in treating HNSCC, and the aforementioned genes can potentially be used as surrogate endpoint biomarkers.

A phase II study examining the feasibility of long-term and low-dose oral capecitabine in newly diagnosed head and neck squamous cell carcinoma after surgery, radiation, and/or chemotherapy

6053

Background: In advanced head and neck squamous cell carcinoma (HNSCC), the five-year survival rate is less than 40%. Although the efficacy and tolerability of continuous IV 5-Fluorouracil (5FU) therapy has been established in HNSCC, the feasibility and tolerability of long-term therapy of oral capecitabine has not been established in HNSCC. Our primary objective is to assess the feasibility of treating patients with squamous cell carcinoma of the head and neck (HNSCC) with adjuvant Capecitabine after undergone definitive treatment. The secondary objectives are to estimate time to recurrence, local-regional control and survival rates along with incidence of second primary tumors. Methods: Eligible patients with newly diagnosed locally advanced HNSCC received capecitabine 1,000 mg orally once daily for one year, after undergone definitive treatment. Patients’ compliance with oral capecitabine as will as the side effects profile was evaluated on monthly basis over the first 12 months. Feasibility, survival, progression and progression free survival were measured over 36 months. Results: Thirty five patients were enrolled in the study. 17 patients had stage IV b, 7 had stage III, and 5 had unknown primary HNSCC. All but one took at least 60% of dispensed tablets. Twenty six patients completed at least 7 months of capecitabine. Sixteen patients completed at least 10 month of capecitabine. Two years overall survival rate was 97%. Three years progression free survival was 86%. Conclusions: Adjuvant capecitabine in locally advanced HNSCC is a feasible approach with minimum side effects. A favorable 3-year progression-free survival was found as compare to historical results. We recommend a randomized phase III trail to examine the effect of one year of adjuvant capecitabine versus placebo in locally advanced HNSCC after definitive treatment.

No significant financial relationships to disclose.