{'fraction_non_alphanumeric': 0.047139403706688156, 'fraction_numerical': 0.04754230459307011, 'mean_word_length': 4.6819221967963385, 'pattern_counts': {'":': 0, '<': 2, '<?xml version=': 0, '>': 1, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Effect of oxaliplatin-capecitabine first-line chemotherapy and tumor response on serum proteomic profiles in advanced colorectal cancer and identification of diagnostic biomarkers.

3603 Background: Colorectal cancer (CRC) is the third most common cause of cancer related death. Prognosis is highly dependent on stage at diagnosis making early diagnosis mandatory. Previously we identified serum biomarkers for CRC, by comparing serum from CRC patients and healthy controls, using SELDI-TOF mass spectrometry.


METHODS
We validated our identified biomarkers and assessed the effect of first-line oxaliplatin (130 mg/m2 day 1, q21)-capecitabine (1000 mg/m2 d1-14, q21) therapy by prospective standardized serum sampling at < 2 weeks prior to start of chemotherapy and serially before each chemotherapy cycle in patients with advanced CRC. Samples were drawn according to standardized protocol, centrifuged within 1 hour and stored at -30°C. After thawing they were analyzed with SELDI-TOF MS on CM10 chips at pH 5. Healthy control subjects were matched according to age, gender and time of serum collection. For serial analysis the time points T: 0, 6, 12 and 18 - 24 weeks were used. All patients had given written consent, had WHO PS ≤ 2 and measurable disease, according to RECIST criteria, and/or were evaluable by CEA.


RESULTS
In total 42 patients (mean age: 57 years; range: 37 - 73; male 62%), were treated between 06/2003 and 09/2005. All patients were previously untreated except 8 patients who had received radiation or chemo-radiation for rectal carcinoma (all > 6 months). Median follow up was 45 weeks and median number of courses was 5.5 (range: 1 -10). Response rate was 46%; PR in 19, SD in 12 and PD in 10 patients, respectively (1 not evaluable) and median overall survival was 10.5 months. We identified 6 peptides/proteins (m/z: 31948, 8078, 28101 (apolipoprotein A-I), 7970, 5912 and 12861 Da, respectively (in order of significance) discriminating between CRC and healthy controls (p < 0.001). In a serial analysis of the patients a peptide, with m/z: 5.9-kDa (most likely fibrinogen split product) declined, during chemotherapy in some responsive patients, but apolipoprotein A-I appeared not to change.


CONCLUSIONS
We confirmed our previous identification of apolipoprotein A-I (m/z: 28-kDa) as a potential biomarker for CRC and suggest a peptide with m/z: 5.9-kDa as a potential biomarker of response. No significant financial relationships to disclose.