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The mitogen-activated protein kinase (MAPK)/extracellular signal -regulated kinase (ERK) pathway has a master control role in various cancer-related biological processes as cell growth, proliferation, differentiation, migration, and apoptosis. It also regulates many transcription factors that control microRNAs (miRNAs) and their biosynthetic machinery. To investigate on the still poorly characterised global involvement of miRNAs within the pathway, we profiled the expression of 745 miRNAs in three colorectal cancer (CRC) cell lines after blocking the pathway with three different inhibitors. This allowed the identification of two classes of post-treatment differentially expressed (DE) miRNAs: (1) common DE miRNAs in all CRC lines after treatment with a specific inhibitor (class A); (2) DE miRNAs in a single CRC line after treatment with all three inhibitors (class B). By determining the molecular targets, biological roles, network position of chosen miRNAs from class A (miR-372, miR-663b, miR-1226*) and class B (miR-92a-1*, miR-135b*, miR-720), we experimentally demonstrated that they are involved in cell proliferation, migration, apoptosis, and globally affect the regulation circuits centred on MAPK/ERK signaling. Interestingly, the levels of miR-92a-1*, miR-135b*, miR-372, miR-720 are significantly higher in biopsies from CRC patients than in normal controls; they also are significantly higher in CRC patients with mutated KRAS than in those with wild-type genotypes (Wilcoxon test, p < 0.05): the latter could be a downstream effect of ERK pathway overactivation, triggered by KRAS mutations. Finally, our functional data strongly suggest the following miRNA/target pairs: miR-92a-1*/PTEN-SOCS5; miR-135b*/LATS2; miR-372/TXNIP; miR-663b/CCND2. Altogether, these results contribute to deepen current knowledge on still uncharacterized features of MAPK/ERK pathway, pinpointing new oncomiRs in CRC and allowing their translation into clinical practice and CRC therapy. [ABSTRACT FROM AUTHOR]

Vascular tumors of the ovary are very rare. We report a case of ovarian hemangioma in a patient treated with tamoxifen for breast ductal carcinoma. CD31 and CD34 immunoreactivity confirmed the vascular origin of the tumor. It is interesting to note that estrogen and progesterone receptors were negative in endothelial cells of the hemangioma, but were positive in stromal ovarian cells. Tamoxifen is a synthetic, non-steroidal, anti-estrogenic drug widely used as adjuvant therapy for pre- and post-menopausal, early and metastatic, breast cancer patients with positive estrogen receptor proteins. The mechanism of action of tamoxifen in stimulating the development and/or growth of ovarian hemangioma is unknown. We may speculate that its prolonged, estrogenic effect on the ovary may be one of the stimulating factor. [ABSTRACT FROM AUTHOR]

We report a case of bilateral ovarian ossifications with images that mimic stone formations. A 65-year-old woman presented with a 2-year history of pelvic pain. Computed tomographic scan and pelvic ultrasound identified an enlarged uterus with two calcified lesions interpreted as leiomyomas. Surgical exploration revealed two ovaries with a cystic appearance and stony hard areas. The cyst contents consisted of chocolate-colored material. The pathologic findings were compatible with benign bilateral ovarian endometriotic cysts with extensive ossification. The pelvic pain resolved completely after the surgery. Though the cause of this rare case remains unknown, recognition of cysts with a content of chocolate-colored material and pigment-laden histiocytes allowed us to make the diagnosis of bilateral ovarian endometriotic cysts with extensive ossification. Complete excision was the treatment of choice. [ABSTRACT FROM AUTHOR]