Faculty Bibliography

Significant differences, including epidemiologic, clinical, pathologic and genetic, exist between Asian and Caucasian prostate cancer. Detailed pathologic data are, however, scarce. We studied in detail and compared the pathological features of prostate cancer in radical prostatectomy specimens in 228 patients (117 Japan, 111 US). Japanese prostate cancer had a higher Gleason grade group (mean 2.67 vs. 2.42 US, P < 0.05), but lower pathological stage (72 % pT2 and 28 % pT3 vs 55 % pT2 and 45 % pT3 US, P < 0.05). Japanese cancer showed significantly more tumor foci (3.8 vs 2.9 US, P < 0.05), and higher incidence of bilateral significant disease (81.3 % vs. 66.7 % US, P < 0.05). The dominant tumor nodules in Japanese cases had higher Gleason grade group (mean 2.73 vs. 2.40 US, P < 0.05). The incidence of intraductal carcinoma was significantly higher in Japanese patients (35.3 % vs. 12.6 % US, P < 0.01), which was independent of Gleason score (7: 30.9 % Japan vs 11.8 % US, P < 0.01; >/= 8: 87.5 % Japan vs 28.6 % US, P < 0.01) and tumor stage (pT2: 24.1 % Japan vs 6.6 % US, P < 0.01; pT3: 62.9 % Japan vs 20 % US, P < 0.01). These findings demonstrate distinct pathological features in prostate cancer between Japanese and Caucasian patients, and may have important diagnostic and therapeutic implications.

Squamous cell carcinoma (SCC) and keratoacanthoma (KA; SCC/KA) research has been hampered mainly by our lack of understanding the underlying genetic and epigenetic alterations associated with SCC/KA development, as well as the lack of animal models that faithfully recapitulate histopathologic features of human SCC/KA. Here, we show that TPL2 overexpression induced both cell transformation in immortalized human keratinocytes and SCC and KA-like cutaneous SCC (cSCC) development in mice. Mechanistically, activation of TPL2 downstream signaling pathways such as MEK/ERK MAPK, mTOR, NF-kappaB, and p38 MAPK leads to TPL2-mediated cell transformation in immortalized human keratinocytes and tumorigenesis in mice. Most importantly, TPL2 overexpression is required for iTPL2 TG-driven SCC and KA-like cSCC tumor maintenance, validating TPL2 as a possible drug target for the treatment of SCC/KA. Finally, we verified that TPL2 is overexpressed in human cutaneous metastatic SCC and KA clinical specimens compared with normal skin. Taken together, our results establish TPL2 as an oncogenic driver in SCC/KA development. Cancer Res; 76(22); 1-11. (c)2016 AACR.

The current substage classification of pT2 prostate cancer (AJCC, 7th edition, 2010) into pT2a (unilateral tumors <1/2 of lobe), pT2b (unilateral tumors >/=1/2 of lobe) and pT2c (bilateral tumors) is of questionable relevance. Many studies show no difference in prognosis between substages, and incidence of pT2b prostate cancer is low. Other classification systems have been proposed based on tumor volume, as measured by dominant nodule size or tumor percentage. We characterized pT2b tumors and assessed utility of current pT2 substaging in predicting biochemical recurrence-free survival after radical prostatectomy and compared with different substaging methods based on tumor volume. Patients with pT2 tumors were selected among patients who underwent radical prostatectomy from 1998 to 2008. Dominant nodule size was dichotomized as <1.6 cm vs. >/=1.6 cm. Tumor percentage was dichotomized as 25%. Kaplan-Meier analysis and multivariate Cox proportional hazard regression models were used to evaluate pathological parameters predictive of biochemical recurrence-free survival. 785 patients met criteria, of which 145 (18.5%) were pT2a, 15 (1.9%) were pT2b and 625 (79.6%) were pT2c. The pT2 substages were not significant predictors of biochemical recurrence-free survival on univariate or multivariate analysis. In a multivariate model, tumor percentage>25% (p=0.002) was associated with decreased biochemical recurrence-free survival. In patients with stage pT2 prostate cancer, the current substaging method lacks predictive value for biochemical recurrence-free survival after accounting for other pathologic and clinical predictors. However, tumor percentage (25%) is a promising approach to substaging of pT2 prostate cancer.

Prediction of biochemical recurrence risk of prostate cancer following radical prostatectomy is critical for determining whether the patient would benefit from adjuvant treatments. Various nomograms exist today for identifying individuals at higher risk for recurrence; however, an optimistic under-estimation of recurrence risk is a common problem associated with these methods. We previously showed that anisotropy of light scattering measured using quantitative phase imaging, in the stromal layer adjacent to cancerous glands, is predictive of recurrence. That nested-case controlled study consisted of specimens specifically chosen such that the current prognostic methods fail. Here we report on validating the utility of optical anisotropy for prediction of prostate cancer recurrence in a general population of 192 patients, with 17% probability of recurrence. Our results show that our method can identify recurrent cases with 73% sensitivity and 72% specificity, which is comparable to that of CAPRA-S, a current state of the art method, in the same population. However, our results show that optical anisotropy outperforms CAPRA-S for patients with Gleason grades 7-10. In essence, we demonstrate that anisotropy is a better biomarker for identifying high-risk cases, while Gleason grade is better suited for selecting non-recurrence. Therefore, we propose that anisotropy and current techniques be used together to maximize prediction accuracy.