Open AccessHigh antitumor activity of pladienolide B and its derivative in gastric cancer
Author(s) -
Sato Momoko,
Muguruma Naoki,
Nakagawa Tadahiko,
Okamoto Koichi,
Kimura Tetsuo,
Kitamura Shinji,
Yano Hiromi,
Sannomiya Katsutaka,
Goji Takahiro,
Miyamoto Hiroshi,
Okahisa Toshiya,
Mikasa Hiroaki,
Wada Satoshi,
Iwata Masao,
Takayama Tetsuji
Publication year - 2014
Publication title -
cancer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 1347-9032
DOI - 10.1111/cas.12317
Subject(s) - cancer , medicine , cancer cell , cancer research , pathology
The antitumor activity of pladienolide B, a novel splicing inhibitor, against gastric cancer is totally unknown and no predictive biomarker of pladienolide B efficacy has been reported. We investigated the antitumor activity of pladienolide B and its derivative on gastric cancer cell lines and primary cultured cancer cells from carcinomatous ascites of gastric cancer patients. The effect of pladienolide B and its derivative on six gastric cancer cell lines was investigated using a MTT assay and the mean IC 50 values determined to be 1.6 ± 1.2 (range, 0.6–4.0) and 1.2 ± 1.1 (range, 0.4–3.4) nM, respectively, suggesting strong antitumor activity against gastric cancer. The mean IC 50 value of pladienolide B derivative against primary cultured cells from 12 gastric cancer patients was 4.9 ± 4.7 nM, indicative of high antitumor activity. When 18 SCID mice xenografted with primary cultured cells from three patients were administered the pladienolide B derivative intraperitoneally, all tumors completely disappeared within 2 weeks after treatment. Histological examination revealed a pathological complete response for all tumors. In the xenograft tumors after treatment with pladienolide B derivative, immature mRNA were detected and apoptotic cells were observed. When the expressions of cell‐cycle proteins p16 and cyclin E in biopsied gastric cancer specimens were examined using immunohisctochemistry, positivities for p16 and cyclin E were significantly and marginally higher, respectively, in the low‐ IC 50 group compared with the high‐ IC 50 group, suggesting the possibility that they might be useful as predictive biomarkers for pladienolide B. In conclusion, pladienolide B was very active against gastric cancer via a mechanism involving splicing impairment and apoptosis induction.