Cell Adhesion Molecules Affected by Ionizing Radiation and Estrogen in an Experimental Breast Cancer Model.

Cancer develops in a multi-step process where environmental carcinogenic exposure is a primary etiological component, and where cell-cell communication governs the biological activities of tissues. Identifying the molecular genes that regulate this process is essential to targeting metastatic breast cancer. Ionizing radiation can modify and damage DNA, RNA, and cell membrane components such as lipids and proteins by direct ionization. Comparing differential gene expression can help to determine the effect of radiation and estrogens on cell adhesion. An in vitro experimental breast cancer model was developed by exposure of the immortalized human breast epithelial cell line MCF-10F to low doses of high linear energy transfer α particle radiation and subsequent growth in the presence of 17ß-estradiol. The MCF-10F cell line was analyzed in different stages of transformation that showed gradual phenotypic changes including altered morphology, increase in cell proliferation relative to the control, anchorage-independent growth, and invasive capability before becoming tumorigenic in nude mice. This model was used to determine genes associated with cell adhesion and communication such as E-cadherin, the desmocollin 3, the gap junction protein alpha 1, the Integrin alpha 6, the Integrin beta 6, the Keratin 14, Keratin 16, Keratin 17, Keratin 6B, and the laminin beta 3. Results indicated that most genes had greater expression in the tumorigenic cell line Tumor2 derived from the athymic animal than the Alpha3, a non-tumorigenic cell line exposed only to radiation, indicating that altered expression levels of adhesion molecules depended on estrogen. There is a significant need for experimental model systems that facilitate the study of cell plasticity to assess the importance of estrogens in modulating the biology of cancer cells.

Characterization of cervical cancer stem cell-like cells: phenotyping, stemness, and human papilloma virus co-receptor expression.

Cancer stem cells (CSC) exhibit high tumorigenic capacity in several tumor models. We have now determined an extended phenotype for cervical cancer stem cells. Our results showed increased CK-17, p63+, AII+, CD49f+ expression in these cells, together with higher Aldehyde dehydrogenase (ALDHbright)activity in Cervical CSC (CCSC) enriched in cervospheres. An increase in stem cell markers, represented by OCT-4, Nanog, and ß-catenin proteins, was also observed, indicating that under our culture conditions, CCSC are enriched in cervospheres, as compared to monolayer cultures. In addition, we were able to show that an increased ALDHbright activity correlated with higher tumorigenic activity. Flow cytometry and immunflorescence assays demonstrated that CCSC in cervosphere cultures contain a sub-population of cells that contain Annexin II, a Human papillomavirus (HPV) co-receptor. Taken together, under our conditions there is an increase in the number of CCSC in cervosphere cultures which exhibit the following phenotype: CK-17, p63+, AII+, CD49f+ and high ALDH activity, which in turn correlates with higher tumorigenicity. The presence of Annexin II and CD49f in CCSC opens the possibility that normal cervical stem cells could be the initial target of infection by high risk HPV.

Multiple cystic disease: K17 dysfunction?

Our patient is a 29-year-old woman without any previous disease who presented with different kinds of lesions on her face, neck, and chest. She first noticed the lesions 10 years ago and, since that time, they have become more numerous. She has no affected relatives. On physical examination, she had multiple cystic lesions on her neck, chest, and vulva, which were between 0.3 cm and 1 cm and skin-colored or yellowish (Figure 1). She presented with small, white papules on her face measuring approximately 0.2 cm, localized on her forehead and cheeks. Some of these papules had a blueish appearance (Figure 2). She also presented clinically typical eruptive syringomas on her upper and lower eyelids and neck and multiple facial milia. Finally, a sacrococcygeal pilonidal cyst was diagnosed and surgically removed. Her nails and teeth were clinically normal. Biopsies of each kind of lesion were performed, with the following results: (1) neck cystic lesion: steatocystoma; (2) small, white facial papule: eccrine hidrocystoma; (3) blueish facial papule: apocrine hidrocystoma; and (4) small neck papule: syringoma (Figure 3). With these findings, our diagnosis was steatocystoma multiplex with multiple eccrine and apocrine hidrocystomas, eruptive syringomas, and sacrococcygeal pilonidal cyst.

Do you know this syndrome? Pachyonychia congenita.

Pachyonychia Congenita is a rare genodermatosis of keratinization, first described in 1906 by Jadassohn and Lewandowsky. Besides not being well known, phenotypic variability and oligosymptomatic subtypes make the diagnosis difficult. We report a family with three generations affected, until recently not diagnosed. The active search for familial cases in patients with suspicious manifestations and identification of peculiar characteristics of its subtypes, as multiplex steatocystoma, provide early clinical diagnosis. In addition, nurture the family counseling and informations about prognosis.