To evaluate the impact of the presence of endometrioma and laparoscopic cystectomy on ovarian reserve as assessed by serum anti-Müllerian hormone (AMH) level. In addition, factors related to the decline in ovarian reserve were analyzed. From June 2013 to January 2014, we prospectively included 40 women with endometriomas as the study group (group A), 36 women with tubal factor infertilities as control group 1 (group B) and 22 women with the other benign ovarian cysts as control group 2 (group C). The women with ovarian cysts underwent laparoscopic cystectomy. Serum AMH levels were determined preoperatively and at 1 month after surgery. The endometrioma group had lower AMH levels (1.53 ± 1.37 ng/ml) compared with the other benign ovarian cyst group (2.20 ± 1.23 ng/ml) and the tubal factor infertility group (2.82 ± 1.74 ng/ml). The rate of serum AMH decline 1 month after surgery in the endometrioma group (0.62 ± 0.35) was larger than the decline in the other benign ovarian cyst group (0.32 ± 0.30). The preoperative AMH level showed a significant correlation with patient age (group A, r = −0.32; group B, r = −0.54; group C, r = −0.71); there was a statistically significant correlation between the rate of serum AMH decline and endometrioma diameter as well as with the preoperative serum AMH level. In addition, the rate of serum AMH decline was larger for bilateral endometriomas than for unilateral endometriomas, but there was no similar correlation in the other benign ovarian cyst group. The rate of AMH decline after surgery in the subgroup of >7 cm was significantly higher than in the subgroup of ≤7 cm. Ovarian endometriomas per se may damage ovarian reserve, and cystectomy of endometriomas may cause greater damage to ovarian reserve compared with other benign ovarian cysts. The operation-related damage to the ovarian reserve was positively related to whether the endometriomas were bilateral, as well as cyst size (especially for cysts >7 cm), but was negatively related to the preoperative serum AMH level. Age was a negative factor that affected the ovarian reserve.

Poly C Binding Protein 1 (PCBP1) is an RNA-binding protein that binds and regulates translational activity of subsets of cellular mRNAs. Depletion of PCBP1 is implicated in various carcinomas, but the underlying mechanism in tumorigenesis remains elusive. We performed a transcriptome-wide screen to identify novel bounding mRNA of PCBP1. The bind regions between PCBP1 with target mRNA were investigated by using point mutation and luciferase assay. Cell proliferation, cell cycle, tumorigenesis and cell apoptosis were also evaluated in ovary and colon cancer cell lines. The mechanism that PCBP1 affects p27 was analyzed by mRNA stability and ribosome profiling assays. We analyzed PCBP1 and p27 expression in ovary, colon and renal tumor samples and adjacent non-tumor tissues using RT-PCR, Western Blotting and immunohistochemistry. The prognostic significance of PCBP1 and p27 also analyzed using online databases. We identified cell cycle inhibitor p27Kip1 (p27) as a novel PCBP1-bound transcript. We then demonstrated that binding of PCBP1 to p27 3’UTR via its KH1 domain mainly stabilizes p27 mRNA, while enhances its translation to fuel p27 expression, prior to p27 protein degradation. The upregulated p27 consequently inhibits cell proliferation, cell cycle progression and tumorigenesis, whereas promotes cell apoptosis under paclitaxel treatment. Conversely, knockdown of PCBP1 in turn compromises p27 mRNA stability, leading to lower p27 level and tumorigenesis in vivo. Moreover, forced depletion of p27 counteracts the tumor suppressive ability of PCBP1 in the same PCBP1 over-expressing cells. Physiologically, we showed that decreases of both p27 mRNA and its protein expressions are well correlated to PCBP1 depletion in ovary, colon and renal tumor samples, independent of the p27 ubiquitin ligase Skp2 level. Correlation of PCBP1 with p27 is also found in the tamoxifen, doxorubincin and lapatinib resistant breast cancer cells of GEO database. Our results thereby indicate that loss of PCBP1 expression firstly attenuates p27 expression at post-transcriptional level, and subsequently promotes carcinogenesis. PCBP1 could be used as a diagnostic marker to cancer patients.

BACKGROUND: Internal tandem duplication of FMS‐like tyrosine kinase (FLT3‐ITD) is well known to be involved in acute myeloid leukemia (AML) progression, but FLT3‐ITD–negative AML cases account for 70% to 80% of AML, and the mechanisms underlying their pathology remain unclear. This study identifies protein tyrosine phophatase PRL‐3 as a key mediator of FLT3‐ITD–negative AML.METHODS: A total of 112 FLT3‐ITD–negative AML patients were sampled between 2010 and 2013, and the occurrence of PRL‐3 hyperexpression in FLT3‐ITD–negative AML was evaluated by multivariate probit regression analysis. Overexpression or depletion of endogenous PRL‐3 expression with the specific small interfering RNAs was performed to investigate the role of PRL‐3 in AML progression. Xenograft models were also used to confirm the oncogenic role of PRL‐3.RESULTS: Compared to healthy donors, PRL‐3 is upregulated more than 3‐fold in 40.2% of FLT3‐ITD–negative AML patients. PRL‐3 expression level is adversely correlated to the overall survival of the AML patients, and the AML relapses accompany with re‐upregulation of PRL‐3. Mechanistically, aberrant PRL‐3 expression promoted cell cycle progression and enhanced the antiapoptotic machinery of AML cells to drug cytotoxicity through downregulation of p21 and upregulation of Cyclin D1 and CDK2 and activation of STAT5 and AKT. Depletion of endogenous PRL‐3 sensitizes AML cells to therapeutic drugs, concomitant with apoptosis by upregulation of cleaved PARP (poly ADP ribose polymerase) and apoptosis‐related caspases. Xenograft assays further confirmed PRL‐3's oncogenic role in leukemogenesis.CONCLUSIONS: Our results demonstrated that PRL‐3 is a novel independent crucial player in both FLT3‐ITD–positive and FLT3‐ITD–negative AML and could be a potential therapeutic target. Cancer 2014;120:2130–2141. © 2014 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

Acquired chemotherapy resistance is one of the main culprits in the relapse of breast cancer. But the underlying mechanism of chemotherapy resistance remains elusive. Here, we demonstrate that a small adaptor protein, SH3BGRL, is not only elevated in the majority of breast cancer patients but also has relevance with the relapse and poor prognosis of breast cancer patients. Functionally, SH3BGRL upregulation enhances the chemoresistance of breast cancer cells to the first-line doxorubicin treatment through macroautophagic/autophagic protection. Mechanistically, SH3BGRL can unexpectedly bind to ribosomal subunits to enhance PIK3C3 translation efficiency and sustain ATG12 stability. Therefore, inhibition of autophagy or silence of PIK3C3 or ATG12 can effectively block the driving effect of SH3BGRL on doxorubicin resistance of breast cancer cells in vitro and in vivo. We also validate that SH3BGRL expression is positively correlated with that of PIK3C3 or ATG12, as well as the constitutive occurrence of autophagy in clinical breast cancer tissues. Taken together, our data reveal that SH3BGRL upregulation would be a key driver to the acquired chemotherapy resistance through autophagy enhancement in breast cancer while targeting SH3BGRL could be a potential therapeutic strategy against breast cancer. Abbreviations: ABCs: ATP-binding cassette transporters; Act D: actinomycin D; ACTB/β-actin: actin beta; ATG: autophagy-related; Baf A₁: bafilomycin A₁; CASP3: caspase 3; CHX: cycloheximide; CQ: chloroquine; Dox: doxorubicin; FBS: fetal bovine serum; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GEO: gene expression omnibus; GFP: green fluorescent protein; G6PD: glucose-6-phosphate dehydrogenase; GSEA: gene set enrichment analysis; IHC: immunochemistry; KEGG: Kyoto Encyclopedia of Genes and Genomes; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; 3-MA: 3-methyladenine; mRNA: messenger RNA; PIK3C3: phosphatidylinositol 3-kinase catalytic subunit type 3; SH3BGRL: SH3 domain binding glutamate-rich protein-like; SQSTM1/p62: sequestosome 1; ULK1: unc-51 like autophagy activating kinase 1