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Initially correlated with hematopoietic precursors, the surface expression of CD133 was also found in epithelial and nonepithelial cells from adult tissues in which it has been associated with a number of biological events. CD133 is expressed in solid tumors as well, including breast cancer, in which most of the studies have been focused on its use as a surface marker for the detection of cells with stem-like properties (i.e., cancer stem cells (CSCs)). Differently with other solid tumors, very limited and in part controversial are the information about the significance of CD133 in breast cancer, the most common malignancy among women in industrialized countries. In this review, we summarize the latest findings about the implication of CD133 in breast tumors, highlighting its role in tumor cells with a triple negative phenotype in which it directly regulates the expression of proteins involved in metastasis and drug resistance. We provide updates about the prognostic role of CD133, underlining its value as an indicator of increased malignancy of both noninvasive and invasive breast tumor cells. The molecular mechanisms at the basis of the regulation of CD133 levels in breast tumors have also been reviewed, highlighting experimental strategies capable to restrain its level that could be taken into account to reduce malignancy and/or to prevent the progression of breast tumors.

In 2016 an exhibition on the anatomical waxes of the University of Ferrara was organized by SMA (Museum System of the University). This exhibition displayed the models of the human body which were produced at the end of the 18th century by Giovanni Tumiati and Giuseppe Chiappi for the former’s teaching of obstetrics and which have been restored in the last few years thanks to a collaboration between the Universities of Ferrara and Cagliari. The restoration of the models and the preparation of the exhibition have been the occasion for some important discoveries on the characteristic traits of the models and their makers., I castelli di Yale online, volume V, numero 2, 2017

During prostate cancer progression cancer cells undergo a variety of molecular alterations that lead to the acquisition of uncontrolled growth properties. One such set of molecular alterations is mediated by the PI3K/Akt signaling pathway. Here, we describe a regulatory system that modulates the phosphoinosited 3-kinase/Akt (PI3K/Akt) pathway downstream of secreted Clusterin (sCLU) in normal and cancer prostate cells. The overexpression of sCLU is very frequent in prostate cancer, and can lead to Akt-activation. This prompted us to investigate how sCLU overexpression influences PI3K/Akt signaling network in a study model represented by human epithelial prostate PNT1A cells stably transfected with sCLU or with empty vector alone. We found that CLU cells show a marked differential phosphorylation of several members of the PI3K/Akt cascade, and in particular of Akt2. Moreover, we found that the phosphatase PHLPP1, known to dephosphorylate Akt2 at S473, is severely downregulated in CLU compared to MOCK cells. We thus investigated whether sCLU alters PHLPP1 protein stability or expression. Our results indicate that sCLU indeed stimulates PHLPP1 degradation by β-TrCP. Interestingly, we further demonstrated that sCLU alters also PHLPP1 through the negative regulator miR-190. Next, because sCLU has been reported to inhibit or to stimulate the aggressive behavior of cancer cells depending on the cell model, we investigated the effects of CLU overexpression or addition of recombinant Clusterin to the medium on cell migration and invasion in PNT1A cell line, which is not expected to display an invasive phenotype, and in the cancer prostate epithelial cell lines LNCaP and PC3. The result was extremely clear: not only CLU overexpression gives PNT1A cells the same behavior of wild-type PC3 cells, but also increases the migration and invasion index of all the above cell models by two to four times, compared to controls. As a confirmation, in the same model silencing of Clusterin abrogates migration of CLU cells. Next, the effect of Akt single-isoform silencing on cell migration was explored. While silencing of Akt1 affected migration only slightly, silencing of Akt2 prevented migration of both MOCK and CLU cells completely. The same result was obtained by pharmacological inhibition of Akt2. All together our results, clearly demonstrate for the first time that Clusterin can switch the low migration phenotype of normal prostate cells towards a high migration phenotype through the modulation of the expression of the PHLPP1 and, in turn, the activity of Akt2., Italian Journal of Anatomy and Embryology, Vol. 122, No. 1 (Supplement) 2017

Reduced oxygen availability plays a crucial role in malignancy of solid tumors, including breast cancer. Even if the presence of hypoxic areas is common in all breast lesions, no data clearly correlate low oxygenation with the acquisition of malignant features by non-invasive cells, particularly by cells from ductal carcinoma in situ (DCIS), the most frequently diagnosed tumor in women in industrialized countries [1]. We demonstrated that 96 hours of culture under moderate hypoxia is sufficient to induce in DCIS-derived cells motility and epithelial-to-mesenchymal transition (EMT) and to enlarge the number of cells expressing the stem cell marker CD133, indicative of their increased malignant potential. Administration of all-trans retinoic acid (ATRA), a well-known anti-leukemic drug with an anti-tumor role in invasive breast tumor cells [2], supports the epithelial phenotype of DCIS-derived cells cultured under hypoxia and reduces the number of CD133 positive cells, abrogating almost completely the effects of poor oxygenation. In DCIS-derived cells, as in leukemic cells, ATRA up-regulates the β2 isoform of PI-PLC (PLC-β2), ectopically expressed in invasive breast tumors in which counteracts the effects of hypoxia on both EMT and CD133 levels [3]. This suggests that the mechanisms triggered by ATRA in non-invasive breast tumor cells cultured under hypoxia may, at least in part, depend on PLC-β2 activity. Overall, we assigned to hypoxia a role in increasing the malignant potential of DCIS-derived cells and identified in ATRA, currently used in treating acute promyelocytic leukemia (APL), an agonist potentially useful in preventing malignant progression of non-invasive breast lesions with hypoxic areas., Italian Journal of Anatomy and Embryology, Vol. 122, No. 1 (Supplement) 2017

Acute lymphoblastic leukemia (ALL) is a neoplasm of precursor cells committed to the B-cell and T-cell lineages involving bone marrow and blood, with a rapid onset and frequent chemotherapy resistance and refractory relapses (1). Philadelphia chromosome-positive (Ph+) ALL accounts for 25–30% of adult ALL and its incidence increases with age in adults >40 years old. Irrespective of age, the ABL1 fusion genes, among which BCR-ABL1 is the most commonly found, are markers of very poor prognosis. Amplification of the NUP214-ABL1 oncogene can be detected only in patients with T-ALL (2). The PI3K/Akt/mTOR signaling pathway is activated in many solid cancers and in leukemias and plays a crucial role in tumorigenesis. Furthermore, the presence of RTKs (Receptor Tyrosine Kinases) by ABL1 fusion proteins may result in activation of the PI3K/Akt/mTOR axis. T cell malignancies bearing the ABL1 fusion genes are sensitive to many cytotoxic agents, but up to date complete remissions have not been found. In this work we analyzed the effects of three BCR-ABL1 tyrosine kinase inhibitors (TKIs), alone and in combination with a panel of selective PI3K/Akt/mTOR inhibitors, on two NUP214-ABL1 positive T-ALL cell lines, ALL-SIL and PEER that also displayed Akt hyperactivation. Cells were sensitive to anti BCR-ABL1 TKIs Imatinib, Nilotinib and GZD824, that specifically targeted the ABL1 fusion protein, but not the PI3K/Akt/mTOR axis as deducted by a readout of drug efficacy, four drugs against the PI3K/Akt/mTOR cascade, GSK690693, NVP-BGT226 (BGT226), ZSTK474 and Torin-2, showed a relevant cytotoxic efficacy on T-leukemic cells, without affecting the NUP214-ABL1 kinase and related pathway. Dephosphorylation of pAkt and pS6 showed the cytotoxicity of the compounds. Either single or combined administration of drugs against the different targets displayed inhibition of cellular viability which was associated with a concentration-dependent induction of apoptosis, cell cycle arrest in G0/G1 phase and autophagy, having the combined treatments a significant synergistic cytotoxic effect. Co-targeting NUP214-ABL1 fusion gene and PI3K/Akt/mTOR signaling pathway could represent a new and effective pharmacological strategy to improve the outcome in NUP214-ABL1 positive T-ALL., Italian Journal of Anatomy and Embryology, Vol. 121, No. 1 (Supplement) 2016

Ductal carcinoma in situ (DCIS), which represents the most frequently diagnosed tumor in women in industrialized countries, may be a crucial step in the progression of breast lesions to invasive ductal carcinoma (IDC) (1). Among the signaling molecules deregulated in breast tumors, the beta2 isoform of the phosphoinositide-dependent phospholipase C (PLC-b2) strongly correlates with malignancy of invasive tumors and breast tumor-derived cells (2, 3). In breast tumor-derived cell lines cultured under hypoxia, PLC-b2 regulates the levels of cancer stem cell and epithelial-to-mesenchymal transition (EMT) markers (4), suggesting its involvement in breast cancer progression. By using archival FFPE breast tumor samples, we demonstrated that PLC-β2 is up-regulated in DCIS, in which it inversely correlates to the levels of miR-146a, known to act as a tumor suppressor in breast cancer (5). By using the MCF10DCIS cell line, a well-established model of DCIS-derived cells, we demonstrated that the de-regulation of miR-146a is sufficient to modulate the expression of PLC-β2, in turn able to affect the epithelial-to-mesenchymal shift as well as the number of cells expressing CD133. These data indicate that miR-146a and PLC-β2 are members of an intracellular network able to ensure the maintenance of the non-invasive phenotype of DCIS and suggest that alterations in their levels can determine the appearance of an invasive phenotype. The potential prognostic relevance of PLC-β2/miR-146a relationship was investigated in primary DCIS from patients who developed an invasive ductal carcinoma in the contralateral breast. The PLC-β2/miR-146a correlation was found negative in primary DCIS from patients who did not recur and strongly positive in DCIS from patients who developed a contralateral IDC. We propose that the assessment of the correlation between the levels of PLC-β2 and miR-146a in primary DCIS at diagnosis could be beneficial to identify patients with either low or high propensity to develop invasive recurrence. Since a major problem in the management of patients with DCIS is the lack of reliable prognostic markers, our results might be of value in selecting the most appropriate therapies for individual women with non-invasive breast neoplasia., Italian Journal of Anatomy and Embryology, Vol. 121, No. 1 (Supplement) 2016