Induction of Ovarian Leiomyosarcomas in Mice by Conditional Inactivation of Brca1 and p53

gene is often found in patients with inherited breast and ovarian cancer syndrome..associated inherited EOC

International Society of Gynecological Pathologists (ISGyP) Endometrial Cancer Project : Guidelines From the Special Techniques and Ancillary Studies Group:Guidelines From the Special Techniques and Ancillary Studies Group

The aim of this article is to propose guidelines and recommendations in problematic areas in pathologic reporting of endometrial carcinoma (EC) regarding special techniques and ancillary studies. An organizing committee designed a comprehensive survey with different questions related to pathologic features, diagnosis, and prognosis of EC that was sent to all members of the International Society of Gynecological Pathologists. The special techniques/ancillary studies group received 4 different questions to be addressed. Five members of the group reviewed the literature and came up with recommendations and an accompanying text which were discussed and agreed upon by all members of the group. Twelve different recommendations are made. They address the value of immunohistochemistry, ploidy, and molecular analysis for assessing prognosis in EC, the value of steroid hormone receptor analysis to predict response to hormone therapy, and parameters regarding applying immunohistochemistry and molecular tests for assessing mismatch deficiency in EC

Strategies for High-Resolution Imaging of Epithelial Ovarian Cancer by Laparoscopic Nonlinear Microscopy1

Ovarian cancer remains the most frequently lethal of the gynecologic cancers owing to the late detection of this disease. Here, by using human specimens and three mouse models of ovarian cancer, we tested the feasibility of nonlinear imaging approaches, the multiphoton microscopy (MPM) and second harmonic generation (SHG) to serve as complementary tools for ovarian cancer diagnosis. We demonstrate that MPM/SHG of intrinsic tissue emissions allows visualization of unfixed, unsectioned, and unstained tissues at a resolution comparable to that of routinely processed histologic sections. In addition to permitting discrimination between normal and neoplastic tissues according to pathological criteria, the method facilitates morphometric assessment of specimens and detection of very early cellular changes in the ovarian surface epithelium. A red shift in cellular intrinsic fluorescence and collagen structural alterations have been identified as additional cancer-associated changes that are indiscernible by conventional pathologic techniques. Importantly, the feasibility of in vivo laparoscopic MPM/SHG is demonstrated by using a “stick” objective lens. Intravital detection of neoplastic lesions has been further facilitated by low-magnification identification of an indicator for cathepsin activity followed by MPM laparoscopic imaging. Taken together, these results demonstrate that MPM may be translatable to clinical settings as an endoscopic approach suitable for high-resolution optical biopsies as well as a pathology tool for rapid initial assessment of ovarian cancer samples

Mutation of Pten/Mmac1 in mice causes neoplasia in multiple organ systems

Pten/Mmac1+/− heterozygous mice exhibited neoplasms in multiple organs including the endometrium, liver, prostate, gastrointestinal tract, thyroid, and thymus. Loss of the wild-type allele was detected in neoplasms of the thymus and liver. Surprisingly, tumors of the gastrointestinal epithelium developed in association with gut lymphoid tissue. Tumors of the endometrium, thyroid, prostate, and liver were not associated with lymphoid tissue and appeared to be highly mitotic. In addition, these mice have nonneoplastic hyperplasia of lymph nodes that was caused by an inherited defect in apoptosis detected in B cells and macrophages. Examination of peripheral lymphoid tissue including lymphoid aggregates associated with polyps revealed that the normal organization of B and T cells was disrupted in heterozygous animals. Taken together, these data suggest that PTEN is a regulator of apoptosis and proliferation that behaves as a “landscaper” tumor suppressor in the gut and a “gatekeeper” tumor suppressor in other organs

Incidence and latency of reproductive tract tumors in female mice with conditional inactivation of LoxP flanked alleles of <i>Brca1</i> and/or <i>p53</i>.

<p>A) Fraction of tumor free mice after intrabursal injection of Adenovirus-Cre recombinase. B) Genotyping analysis of DNA isolated from <i>Brca1</i>^Δ5-13;<i>p53</i>^Δ2-10 and <i>p53^Δ2-10</i> ovarian tumors. Both the Lox P flanked and excised <i>Brca1</i> and <i>p53</i> alleles were amplified from <i>Brca1</i>^Δ5-13;<i>p53</i>^Δ2-10 tumors (cases 307, 350, 352 355, 397, 399, 411 and 412) and the Lox P flanked and excised <i>p53</i> allele was amplified from the single <i>p53^Δ2-10</i> ovarian tumor (case 627). In each panel the left lane contains a DNA ladder and the sizes of the amplified products (nt) are indicated at the right.</p

Intrabursal injection of Adenovirus results in ovarian surface epithelial cell-restricted infection.

<p>A) Histochemical detection of β-galactosidase expression in tissue sections of ovaries of a wild type mouse that received intrabursal injection of Ad5-CMV-LacZ show staining of the ovarian surface epithelium and absence of staining of the underlying ovarian cortex (panels a and b). Occasional β-galactosidase positive cells were also observed in fallopian tube (panel c) while no staining was observed in a control mouse injected with PBS (panel d). Scale bars in each image represent 100 µm. B) PCR amplification of LoxP containing sites in introns 4 (top) and 13 (bottom) of <i>Brca1</i> in <i>Brca1^LoxP/LoxP</i>, <i>Brca1^wt/wt</i>, <i>Brca1^wt</i>^/Δ5-13 and <i>Brca1^WT/LoxP</i> mice. Genomic DNA was isolated after digestion with proteinase K from the following tissues: liv–liver, t–tail, ut–uterus, ov 30′–ovary after 30 minute digestion and ov 12 h–ovary after 12 hours of digestion. The sizes of the LoxP flanked and wild type (wt) intron 4 and 13 PCR products are indicated. C) PCR amplification of 594 nt excised <i>Brca1</i>^Δ5-13 allele was detected only in the ovary exposed to digestion for 30 minutes and in the genomic DNA isolated from a <i>Brca1^wt</i>^/Δ5-13 mouse.</p

Summary of tumors associated with Cre-mediated inactivation of <i>Brca1</i> and/or <i>p53</i>.

<p>Summary of tumors associated with Cre-mediated inactivation of <i>Brca1</i> and/or <i>p53</i>.</p

Histopathological characterization of ovarian tumors arising in <i>Brca1</i>^Δ5-13;<i>p53</i>^Δ2-10 and <i>p53^Δ2-10</i> mice after intrabursal administration of Ad5-CMV-Cre.

<p>A) Low (panels a, e, and i) and high (panels b, f, and j) magnification of H&E stained sections of tumors isolated from two <i>Brca1</i>^Δ5-13;<i>p53</i>^Δ2-10 mice (cases number 307, panels a–d, and 399, panels e–h) and one <i>p53^Δ2-10</i> mouse (case number 627, panels i-l). Immunohistochemical detection of proliferating cell nuclear antigen (PCNA) shows that all three tumors were highly proliferative (panels c, g, and k). Immunohistochemical staining for p53 (Panels d, h, and l) showing that none of the tumors express p53 protein, consistent with the conditional inactivation of the LoxP-flanked <i>p53</i> allele. B) Immunohistochemical staining of <i>Brca1</i>^Δ5-13;<i>p53</i>^Δ2-10 case number 307, a representative tumor, shows that the tumor is highly proliferative (PCNA staining, panel a), but does not express other common differentiation markers. Immunostaining for α-inhibin (panel b) shows isolated positively staining follicular cells and little or no staining of the tumor cells. Similarly, immunohistochemical detection of markers of lymphoid (CD45, panel c) epithelial (cytokeratins 8 and 19, panels d and e respectively) and stromal (α-smooth muscle actin, panel f) differentiation are not detected in tumor cells. Scale bars in each image represent 100 µm.</p