Purpose: Expression of the PGE2 receptor, EP4, is up-regulated during colorectal carcinogenesis. However the mechanism leading to deregulation of the EP4 receptor is not known. The present study wa...

Purpose: This phase I trial evaluated intraperitoneal (i.p.) pemetrexed, cisplatin, and paclitaxel in optimally debulked ovarian cancer. Experimental Design: Dose escalation of day 1 i.p. pemetrexed accrued three patients to each of five dose levels (60–1,000 mg/m²), along with day 2 i.p. cisplatin (75 mg/m²) and day 8 i.p. paclitaxel (60 mg/m²). The goals were to determine maximum tolerated dose (MTD), 18-month progression-free survival (PFS), and pharmacokinetics of i.p. pemetrexed. Results: Cycles, given every 21 days, had an 80% 6-cycle completion rate. There was minimal grade III toxicity in the first 4 dose levels and remarkably an almost complete absence of peripheral neuropathy and alopecia. At the highest dose level, two of three patients experienced ≥grade III and dose-limiting toxicity (DLT; hematologic, infection, gastrointestinal). There was a pharmacokinetic advantage for i.p. pemetrexed with an intraperitoneal:plasma area under the concentration–time curve ratio of 13-fold. Neither analysis of pharmacokinetic nor homocysteine levels explains the unexpected severity of toxicity in those two patients. On the basis of plasma C_24h levels, the 42 cycles at ≥500 mg/m² i.p. pemetrexed without DLT, the MTD appears to be 500 mg/m². Median PFS is 30.1 months; 18-month PFS is 78.6% (median follow-up 22.4 months). Conclusions: This i.p.-only regimen in front-line ovarian cancer is feasible with PFS in line with recent literature. We suggest phase II trials of this regimen in this population with i.p. pemetrexed at 500 mg/m². The favorable toxicity profile at doses <1,000 mg/m², which needs to be confirmed, appears to compare well with standard combination i.v./i.p. platinum/taxane chemotherapy in this disease. Clin Cancer Res; 18(9); 2668–78. ©2012 AACR.

Senescence is a major response to cancer chemotherapy and has been linked to unfavorable therapy outcomes. Lamin B1 is a component of the nuclear lamina that plays a pivotal role in chromatin stability. Downregulation of lamin B1 represents an established biomarker for cellular senescence. However, the protein expression level of lamin B1 in malignant tissue, particularly of the breast, has not been previously described. In this work, we investigated lamin B1 protein expression in normal breast epithelium, malignant breast tissue (including adjacent non-malignant tissue) and in malignant tissue exposed to neoadjuvant chemotherapy (NAC) using immunohistochemistry (IHC) in three patient groups (n = 15, n = 87, and n = 43, respectively). Our results indicate that lamin B1 mean positive expression was 93% in normal breast epithelium and 88% in malignant breast cells, but significantly decreased (mean: 55%, p < 0.001) in malignant breast tissue after exposure to NAC, suggestive of senescence induction. No significant association between lamin B1 expression and other clinicopathological characteristics or survival of breast cancer patients was recorded. To our knowledge, this is the first report that established the baseline protein expression level of lamin B1 in normal and malignant breast tissue, and its reduction following exposure to chemotherapy. In conclusion, lamin B1 downregulation can be used reliably as a component of multiple biomarker batteries to identify therapy-induced senescence (TIS) in clinical cancer.

Serous endometrial intraepithelial carcinoma (serous EIC) arising in adenomyosis is rare. It may be underrecognized because of its deceiving morphology when embedded in the foci of adenomyosis. Although there is no connection to peritoneal cavity, some cases may be associated with extrauterine disease. It is currently unknown what the etiology for such a disease is. More studies are in need to elucidate the pathogenesis of such a grave malady. We report a series of 5 cases of serous EIC, which may arise in adenomyosis. The 5 cases are in 5 different patients or whom on histopathological examination of their hysterectomy specimens, the finding of adenomyosis involved with serous intraepithelial neoplasia was identified. The finding of interest was the presence of multifoci of adenomyosis; some of those foci were involved in serous EIC. In addition to EIC, lesions of endometrial glandular dysplasia were present in the foci of adenomyosis. To rule out the possibility of endometrial serous carcinoma (ESC) invading into the areas of the adenomyosis, all of the 5 uteri were extensively examined. Among the 5 uteri, the eutopic endometirum showed 1 invasive ESC, 2 serous EIC, and 2 benign resting endometrium without any cancer or precancerous lesions. In 1 uterus with ESC, we did not see any direct spatial connection between the invasive component of ESC and the areas of EIC in the foci of adenomyosis. In 2 uteri with serous EIC within the endometrial cavity, there was a distance of at least 0.5 cm between the lesions within the endometrial cavity and the serous EIC in adenomyosis. The remaining 2 uteri showed no evidence of endometrial malignancy in the endometrial cavity, whereas serous EIC was present only in areas of adenomyosis. Clinicopathologic data including characterized immunohistochemical stainings and p53 gene sequence analysis are presented and clinical significance is discussed.