Phase II Evaluation of 4'EPI-Doxorubicin in Patients with Metastatic Colorectal Carcinoma

Drug Repositioning Based on the Reversal of Gene Expression Signatures Identifies TOP2A as a Therapeutic Target for Rectal Cancer

Rectal cancer is a common disease with high mortality rates and limited therapeutic options. Here we combined the gene expression signatures of rectal cancer patients with the reverse drug-induced gene-expression profiles to identify drug repositioning candidates for cancer therapy. Among the predicted repurposable drugs, topoisomerase II inhibitors (doxorubicin, teniposide, idarubicin, mitoxantrone, and epirubicin) presented a high potential to reverse rectal cancer gene expression signatures. We showed that these drugs effectively reduced the growth of colorectal cancer cell lines closely representing rectal cancer signatures. We also found a clear correlation between topoisomerase 2A (TOP2A) gene copy number or expression levels with the sensitivity to topoisomerase II inhibitors. Furthermore, CRISPR-Cas9 and shRNA screenings confirmed that loss-of-function of the TOP2A has the highest efficacy in reducing cellular proliferation. Finally, we observed significant TOP2A copy number gains and increased expression in independent cohorts of rectal cancer patients. These findings can be translated into clinical practice to evaluate TOP2A status for targeted and personalized therapies based on topoisomerase II inhibitors in rectal cancer patients.

Underpinning the repurposing of anthracyclines towards colorectal cancer: assessment of topoisomerase II alpha gene copy number alterations in colorectal cancer

OBJECTIVE. We propose a repurposing strategy where anthracyclines are reintroduced to a subgroup of patients with metastatic colorectal cancer with the highest likelihood of response. In breast cancer, DNA topoisomerase II alpha gene (TOP2A) alterations predict incremental benefit of anthracyclines, but this association has not been investigated in colorectal cancer. Frequency analysis of TOP2A gene alterations in colorectal cancer and the association with prognosis are evaluated and the challenges of using a TOP2A/CEN-17 FISH probe combination are addressed. MATERIAL AND METHODS. Formalin-fixed, paraffin-embedded material from 154 stage III colorectal cancer patients included in the RANX05 clinical trial was retrospectively assessed for TOP2A gene alterations using FISH. The TOP2A/CEN-17 ratio as well as the TOP2A gene copy number alone was used to define gene alterations and associations between gene status and outcomes were analyzed. RESULTS. TOP2A gene gain was a frequent finding with 9.8 % having a total of ≥4 TOP2A copies per cell. According to the TOP2A/CEN-17 ratio, 10.5 % had TOP2A gene gain. Polysomy or gain of the centromere region of chromosome-17 was not as frequent as reported in breast cancer. No prognostic characteristic of TOP2A was identified. CONCLUSION. TOP2A gene gain is present in numbers relevant to identify a subgroup of patients who may benefit from anthracycline therapy. Based on the present findings, we will initiate a prospective clinical trial designed to evaluate this hypothesis in patients with metastatic colorectal cancer who have failed 5-fluorouracil and oxaliplatin chemotherapy.

Current status of epirubicin (Farmorubicin) in the treatment of solid tumours

Epirubicin (Farmorubicin) is a drug of significant interest in the treatment of a variety of solid tumours and a comprehensive review of reported investigations is given. From experimental and clinical studies it appears that in general doxorubicin and epirubicin exhibit no qualitative, but only some quantitative, differences. Thus, the pharmacokinetic and pharmacodynamic characteristics of the two drugs are essentially similar, as are the tumour spectrum and the level of their clinical efficacies. To achieve haematological equitoxicity of the two drugs the dose of epirubicin should be approximately 20% higher than that of doxorubicin, giving rise to a higher cumulative dose of epirubicin. On the other hand, epirubicin is significantly less cardiotoxic than doxorubicin. Thus, the recommended cumulative dose of doxorubicin is 500 mg/m2 and the corresponding figure for epirubicin is 1,000 mg/m2. For either drug a number of questions are still left open, the most important of which include the questions about optimal treatment schedules and the existence of a clinical relevant dose/efficacy relationship.