The aim of this study was to investigate the seasonal expression of androgen receptor (AR), estrogen receptors α and β (ERα and ERβ) and aromatase cytochrome P450 (P450arom) mRNA and protein by real-time PCR and immunohistochemistry in the wild ground squirrel (WGS) testes. Histologically, all types of spermatogenic cells including mature spermatozoa were identified in the breeding season (April), while spermatogonia and primary spermatocytes were observed in the nonbreeding season (June), and spermatogonia, primary spermatocytes and secondary spermatocytes were found in pre-hibernation (September). AR was present in Leydig cells, peritubular myoid cells and Sertoli cells in the breeding season and pre-hibernation with more intense staining in the breeding season, whereas AR was only found in Leydig cells in the nonbreeding season; P450arom was expressed in Leydig cells, Sertoli cells and germ cells during the breeding season, whereas P450arom was found in Leydig cells and Sertoli cells during pre-hibernation, but P450arom was not present in the nonbreeding season; Stronger immunohistochemical signal for ERα was present in Sertoli cells and Leydig cells during the breeding season; ERβ was only expressed in Leydig cells of the breeding season. Consistent with the immunohistochemical results, the mean mRNA level of AR, P450arom, ERα and ERβ were higher in the testes of the breeding season when compared to pre-hibernation and the nonbreeding season. These results suggested that the seasonal changes in spermatogenesis and testicular recrudescence and regression process in WGSs might be correlated with expression levels of AR, P450arom and ERs, and that estrogen and androgen may play an important autocrine/paracrine role to regulate seasonal testicular function.

In order to elucidate the relationship between androgens and the function of the muskrat (Ondatra zibethicus) scented glands during the breeding season, we investigated immunolocalization of steroidogenic enzymes P450scc, 3βHSD and P450c17 in the muskrat testes and scented glands. Nine adult muskrats were obtained in March (n=3), May (n=3) and July (n=3) 2010. Steroidogenic enzymes were immunolocalized using polyclonal antisera raised against bovine adrenal P450scc, human placental 3βHSD and porcine testicular P450c17. Histologically, all types of spermatogenic cells including mature-phase spermatozoa in seminiferous tubules were observed in all testes. Glandular cells, interstitial cells, epithelial cells and excretory tubules were identified in scented glands during the breeding season. P450scc, 3βHSD and P450c17 were only identified in Leydig cells during the breeding season; P450scc and P450c17 were observed in glandular cells of scented glands, however, 3βHSD was not found in scented glands during the breeding season. These novel findings provide the first evidence showing that scented glands of the muskrats are capable of locally synthesizing androgens and androgens acting via an endocrine, autocrine or paracrine manner may play an important role in scented gland function during the breeding season.

The nerve growth factor (NGF) not only has an essential effect on the nervous system, but also plays an important role in a variety of non-neuronal systems, such as the reproductive system. The aim of this study was to compare the quality and quantity in expression of NGF and its receptors (TrkA and p75) in testes of the wild ground squirrel during the breeding and nonbreeding seasons. Immunolocalization for NGF was detected mainly in Leydig cells and Sertoli cells in testes of the breeding and nonbreeding seasons. The immunoreactivity of TrkA was highest in the elongated spermatids, whereas p75 in spermatogonia and spermatocytes in testes of the breeding season. In the nonbreeding season testes, TrkA showed positive immunostainings in Leydig cells, spermatogonia and primary spermatocytes, while p75 showed positive signals in spermatogonia and primary spermatocytes. Consistent with the immunohistochemical results, the mean mRNA and protein level of NGF and TrkA were higher in the testes of the breeding season than in non-breeding season, and then decreased to a relatively low level in the nonbreeding season. In addition, the concentration of plasma gonadotropins and testosterone were assayed by radioimmunoassay (RIA), and the results showed a significant difference between the breeding and nonbreeding seasons with higher concentrations in breeding season. In conclusion, these results of this study provide the first evidence on the potential involvement of NGF and its receptor, TrkA and p75 in the seasonal spermatogenesis and testicular function change of the wild ground squirrel.

Background: Single hormone receptor positive, especially single progesterone receptor positive (PgR+), although uncommon, is a unneglectable phenomenon given the large patient population. There is dispute as to single PgR positive is truly positive since PgR is a downstream molecule of estrogen receptor and when HER2 is negative at the same time, it is puzzling whether ER-/PgR+/HER2- breast cancer resemble triple negative breast cancer (TNBC) biologically and clinically. However, little is known about that. Therefore, we explore the role of single PgR positive by comparing ER-/PgR+/HER2- breast cancers with TNBCs. Methods: Among 3966 early breast cancer patients operated consecutively in Cancer Hospital, Chinese Academy of Medical Sciences from Jan 2005 to May 2008, 240 (6%) cases were identified as ER-/PgR+/Her2-and 348 (8.7%) cases as TNBCs. Clinicopathological characteristics and survival were analyzed respectively and then compared between 2 subtypes. Results: The average age of diagnosis was 49 yrs in both groups. For ER-/PgR+/HER2- patients, 213(88.8%) patients received adjuvant chemotherapy and 183 (76.3%) patients got adjuvant endocrine therapy. Axillary lymph node involvement was independent poor prognostic factor for Relapse-free survival (RFS) and overall survival (OS) (RFS: HR 1.728,P = 0.001; OS: HR 2.778, P<0.0001). Patients receiving adjuvant endocrine treatment had better survival than patients receiving no endocrine therapy (RFS: HR 0.594, P = 0.086; OS: HR 0.218,P<0.0001). Similarly, axillary lymph node involvement and large tumor size were found to be the poor prognostic factors for TNBC group. When compared with TNBCs, patients with ER-/PgR+/HER2- tumors tended to have lower tumor grade (P = 0.051) and smaller tumor size (P = 0.036). The metastatic patterns were comparable while RFS and OS demonstrated no difference between ER-/PgR+/HER2- and TNBC patients (5-year RFS rate: 80.7% vs 77.4%, P = 0.330; 5-year OS rate: 88.0% vs 85.2%, P = 0.290). Further analysis showed that ER-/PgR+/HER2- patients receiving adjuvant endocrine treatment had more favorable RFS and OS while ER-/PgR+/HER2- patients without endocrine therapy had worse overall survival compared with TNBC patients. Table 1: 5yr RFS and OS in ER-/PgR+/HER2- patients compared with TNBC patients  RFS  OS  5-year RFS rateHR(95%CI)P5-year OS rateHR(95%CI)PER-/PR+/HER2- with endocrine therapy (N = 183)84.0%0.686(0.453-1.038)0.07593.0%0.410(0.219-0.768)0.005ER-/PR+/HER2- without endocrine therapy (N = 57)70.1%1.392(0.824-2.353)0.21771.9%2.166(1.252-3.746)0.006TNBC as control(N = 348)77.4%  85.2%   Conclusions:This is the largest sample size to date looking at patients with ER-/PgR+/HER2- breast cancers specifically. It shows that without endocrine therapy, this group of patients may have worse outcomes than TNBC patients, indicating that it should be regarded as biologically and clinically distinct group of breast cancer and PgR intrinsically does not play a key role. PgR itself is not a good prognostic factor. However, adjuvant endocrine therapy could benefit this group of patients, suggesting estrogen signaling may still work via different pathways which might involve PgR. Further studies should be done to unravel the underlying mechanism. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-06-29.