Stress-Mediated Reprogramming of Prostate Cancer One-Carbon Cycle Drives Disease Progression.

One-carbon (1C) metabolism has a key role in metabolic programming with both mitochondrial (m1C) and cytoplasmic (c1C) components. Here we show that activating transcription factor 4 (ATF4) exclusively activates gene expression involved in m1C, but not the c1C cycle in prostate cancer cells. This includes activation of methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) expression, the central player in the m1C cycle. Consistent with the key role of m1C cycle in prostate cancer, MTHFD2 knockdown inhibited prostate cancer cell growth, prostatosphere formation, and growth of patient-derived xenograft organoids. In addition, therapeutic silencing of MTHFD2 by systemically administered nanoliposomal siRNA profoundly inhibited tumor growth in preclinical prostate cancer mouse models. Consistently, MTHFD2 expression is significantly increased in human prostate cancer, and a gene expression signature based on the m1C cycle has significant prognostic value. Furthermore, MTHFD2 expression is coordinately regulated by ATF4 and the oncoprotein c-MYC, which has been implicated in prostate cancer. These data suggest that the m1C cycle is essential for prostate cancer progression and may serve as a novel biomarker and therapeutic target. SIGNIFICANCE: These findings demonstrate that the mitochondrial, but not cytoplasmic, one-carbon cycle has a key role in prostate cancer cell growth and survival and may serve as a biomarker and/or therapeutic target.

Association Between Proportion of Nuclei With High Chromatin Entropy and Prognosis in Gynecological Cancers.

Background: Nuclear texture analysis measuring differences in chromatin structure has provided prognostic biomarkers in several cancers. There is a need for improved cell-by-cell chromatin analysis to detect nuclei with highly disorganized chromatin. The purpose of this study was to develop a method for detecting nuclei with high chromatin entropy and to evaluate the association between the presence of such deviating nuclei and prognosis. Methods: A new texture-based biomarker that characterizes each cancer based on the proportion of high-chromatin entropy nuclei (<25% vs ≥25%) was developed on a discovery set of 175 uterine sarcomas. The prognostic impact of this biomarker was evaluated on a validation set of 179 uterine sarcomas, as well as on independent validation sets of 246 early-stage ovarian carcinomas and 791 endometrial carcinomas. More than 1 million images of nuclei stained for DNA were included in the study. All statistical tests were two-sided. Results: An increased proportion of high-chromatin entropy nuclei was associated with poor clinical outcome. The biomarker predicted five-year overall survival for uterine sarcoma patients with a hazard ratio (HR) of 2.02 (95% confidence interval [CI] = 1.43 to 2.84), time to recurrence for ovarian cancer patients (HR = 2.91, 95% CI = 1.74 to 4.88), and cancer-specific survival for endometrial cancer patients (HR = 3.74, 95% CI = 2.24 to 6.24). Chromatin entropy was an independent prognostic marker in multivariable analyses with clinicopathological parameters (HR = 1.81, 95% CI = 1.21 to 2.70, for sarcoma; HR = 1.71, 95% CI = 1.01 to 2.90, for ovarian cancer; and HR = 2.03, 95% CI = 1.19 to 3.45, for endometrial cancer). Conclusions: A novel method detected high-chromatin entropy nuclei, and an increased proportion of such nuclei was associated with poor prognosis. Chromatin entropy supplemented existing prognostic markers in multivariable analyses of three gynecological cancer cohorts.

Neuron navigator-2 and cyclin D2 are new candidate prognostic markers in uterine sarcoma.

The objective of this study was to validate the diagnostic and clinical role of four protein products of genes previously found to be differentially expressed in uterine low-grade endometrial stromal sarcoma (LG-ESS) compared to uterine leiomyosarcoma (LMS). Protein expression by immunohistochemistry of transgelin (TGLN), neuron navigator-2 (NAV2), fatty acid binding protein-3 (FABP3), and cyclin D2 (CCND2) was analyzed in 305 uterine sarcomas (231 LMS, 74 LG-ESS). Expression was analyzed for association with clinicopathologic parameters and survival. TGLN (p < 0.001), NAV2 (p < 0.001), and FABP3 (p = 0.005) were overexpressed in LMS compared to LG-ESS, whereas nuclear CCND2 (p < 0.001) was overexpressed in LG-ESS. NAV2 expression was associated with shorter overall survival in patients with LMS (p = 0.037), whereas nuclear CCND2 expression in LG-ESS was significantly related to longer survival (p = 0.012) in univariate analysis. Nuclear CCND2 expression was an independent prognosticator in Cox multivariate analysis (p = 0.023). In conclusion, TGLN, FABP3, NAV2, and nuclear CCND2 aid in differentiating LG-ESS from LMS. NAV2 and CCND2 are novel candidate prognostic markers in LMS and LG-ESS, respectively.

Progesterone Receptor Expression Is an Independent Prognosticator in FIGO Stage I Uterine Leiomyosarcoma.

OBJECTIVES: To analyze the clinical role of hormone receptors in a large uterine sarcomas series with long-term follow-up. METHODS: Protein expression of estrogen receptor (ER) and progesterone receptor (PR) by immunohistochemistry was studied in tissue microarrays from 294 patients diagnosed with uterine sarcoma in Norway from 1970 to 2000 and analyzed for an association with clinicopathologic parameters and outcome. RESULTS: ER and PR were detected in 136 of 291 and 184 of 291 tumors (three noninformative cases each), respectively. Expression was unrelated to histology, patient age, tumor diameter, the degree of atypia, the presence of necrosis or vascular invasion, or mitotic counts. ER and PR expression was unrelated to survival in the analysis of the entire cohort. When survival analysis was confined to stage I leiomyosarcoma (n = 147), higher PR score was significantly related to longer overall survival (OS) (P = .042). Clinicopathologic prognosticators in this group were age (P = .041), tumor diameter (P = .001), and mitotic count (P = .007), with a trend for atypia (P = .087). In Cox multivariate analysis, PR score (P = .019), tumor diameter (P = .013), and mitotic count (P = .002) were independent prognosticators of OS. CONCLUSIONS: Hormone receptor expression is not informative of outcome in the analysis of uterine sarcomas of all stages and histologic types. PR expression identifies patients with longer survival in stage I leiomyosarcoma.

DNA ploidy may be a prognostic marker in stage I and II serous adenocarcinoma of the endometrium.

In patients with serous adenocarcinoma (SAC) of the endometrium, we evaluated the prognostic importance of clinicopathological parameters, DNA ploidy, and immunoexpression of p53, estrogen receptor (ER), progesterone receptor (PR), and Ki-67. In a series of 73 stage I and II SAC, DNA ploidy analysis was performed on hysterectomy specimens using DNA image cytometry. Immunohistochemical analysis of p53, ER, PR, and Ki-67 expression was additionally performed. In the review of the histological slides by three gynecologic pathologists, the presence of a serous component was not agreed upon in 17 (23 %) cases. The remaining 56 cases, consisting of pure SAC or SAC mixed with endometrioid adenocarcinoma, were further analyzed. Tumor recurrence was observed in 14 patients, and 28 patients died during the follow-up period. Patients with diploid (n = 19), aneuploid (n = 29), and tetraploid (n = 8) tumor had 5-year recurrence rates of 10, 38, and 53 %, respectively (p = 0.09). A DNA ploidy parameter, 5c exceeding rate, was found to be a prognostic marker for recurrence (p = 0.03), progression-free survival (p < 0.01), and overall survival (p = 0.02). Immunoexpression of p53, ER, PR, and Ki-67 did not have prognostic value, and the same was true for FIGO stage, lymphovascular invasion, the extent of myometrial invasion, and lymphadenectomy. The histological diagnosis of SAC may be difficult in some cases. Established clinicopathological parameters do not seem to be strong prognosticators in stage I and II disease. A DNA ploidy parameter, 5c exceeding rate, may be a prognostic marker in this patient group and should be further validated in larger series.

DNA ploidy heterogeneity in endometrial carcinoma: comparison between curettage and hysterectomy specimens.

DNA ploidy has been reported to be a prognostic marker for patients with endometrial carcinoma. In this study, DNA ploidy and histologic heterogeneity were evaluated by comparing curettage and hysterectomy specimens in 99 consecutive patients diagnosed with endometrial carcinoma. High-resolution DNA ploidy image analysis and review of histologic specimens were performed. The histologic subtypes were identical in 77 (78%) and differed in 22 (22%) cases. The DNA ploidy results were concordant in the curettage and hysterectomy specimens in 72 (72.7%) and discordant in 27 (27.3%) cases. Histologic heterogeneity was significantly associated with DNA ploidy heterogeneity (P=0.03). On the basis of histologic heterogeneity, DNA ploidy-discordant cases were divided into 2 groups. One group (16.2% of cases) consisted of specimens with similar histology in curettage and hysterectomy, all belonging to the endometrioid subtype. This group showed DNA ploidy discordance because of a DNA diploid peak in 1 specimen and an aneuploid peak (DI=1.05-1.2) in the other. The other group (11.1% of cases) consisted of cases with different histologic subtype or grade and showed a more pronounced DNA ploidy difference (diploid vs. aneuploid with DI>1.2). Our results suggest that the DNA ploidy results of the hysterectomy and curettage specimens are not identical. The difference observed, which we believe reflects the intratumoral heterogeneity, should be taken into account when applying DNA ploidy to endometrial carcinoma specimens.

Gross genomic alterations differ between serous borderline tumors and serous adenocarcinomas--an image cytometric DNA ploidy analysis of 307 cases with histogenetic implications.

Our objective was to study the gross genomic alterations in serous borderline tumors and serous adenocarcinomas of the ovary. A retrospective analysis of 245 serous borderline tumors and 62 serous adenocarcinomas from 249 patients was performed using high-resolution image cytometric DNA ploidy analysis. DNA ploidy status, S-phase fraction, and DNA index were evaluated. The majority of serous borderline tumors were diploid (225/245 cases, 92%). The remaining 8% showed an aneuploid peak predominantly with DNA index of less than 1.4. Grades 2 and 3 serous adenocarcinomas were more often (80%) nondiploid, mostly with DNA index exceeding 1.4. Grade 1 serous adenocarcinomas were an intermediate group, more similar to serous borderline tumors. The S-phase fraction increased from serous borderline tumors (mean = 0.6%) through grade 1 serous adenocarcinomas (mean = 2.8%), being highest in grades 2 and 3 adenocarcinomas (mean = 6.8%). Our findings support the hypothesis that serous borderline tumors and grades 2 and 3 serous adenocarcinomas are genomically different lesions, with grade 1 serous adenocarcinomas being an intermediate group more close to borderline tumors.