演題番号 : O28-1
Preoperative neoadjuvant chemotherapy is considered to be effective for colorectal cancer (CRC) with liver metastasis. Several molecular targeted drugs have shown clinical efficacy in neoadjuvant chemotherapy. At present, there are no biomarkers to predict the effects of molecular targeted drugs in patients with colorectal cancer with liver metastasis. Thus, we performed the present study to explore potential biomarkers for these patients.
We obtained cancer tissue specimens from liver metastasis-bearing CRC patients who received the following preoperative neoadjuvant chemotherapies with molecular targeted drugs: no therapy (n=3), 5-FU + oxaliplatin + anti-EGFR (n=3), and 5-FU + oxaliplatin + anti-VEGF (n=3). In all cases in the three groups, shrinkage of liver metastasis was observed and complete resection of the primary CRC and liver metastases was achieved. We investigated the RNA expression of 84 genes related to cancer drug resistance using an RT-PCR array.
The gene expression of ABCC3, BCL2, CDKN2A, CYP1A1, CYP3A5, ESR1, ESR2, and XPA in the CRC tissue specimens from the 5-FU + oxaliplatin + anti-EGFR group was significantly upregulated (>2-fold) in comparison to the no therapy group. The gene expression of BCL2, CY2C8, CYP2E1, CYP3A5, ERBB4, and RARA in the CRC tissue specimens of the 5-FU + oxaliplatin + anti-VEGF group was significantly upregulated (>2-fold) in comparison to the no therapy group. The MYC gene was the only gene that was significantly upregulated (>2-fold) in CRC tissue specimens from the 5-FU + oxaliplatin + anti-EGFR group in comparison to the 5-FU + oxaliplatin + anti-VEGF group.
MYC upregulation in the primary CRC tissues may be a useful biomarker for selecting anti-EGFR combination therapy in the 5-FU + oxaliplatin neoadjuvant chemotherapy for CRC with liver metastasis.