Ovarian Malignant Mixed Germ Cell Tumor With Prominent Embryoid Bodies (Polyembryoma Background): A Case Report and Literature Review.

Ovarian malignant mixed germ cell tumors are rare tumors occurring in young women. The presence of prominent embryoid bodies in these tumors is extremely uncommon. Herein, we report such a case, with a histomorphologic description and immunohistochemical and fluorescence in situ hybridization analyses.

Phenogenomic heterogeneity of post-transplant plasmablastic lymphomas.

Plasmablastic lymphoma (PBL) is a rare and clinically aggressive neoplasm that typically occurs in immunocompromised individuals, including those with HIV infection and solid organ allograft recipients. Most prior studies have focused on delineating the clinicopathologic features and genetic attributes of HIV-related PBLs, where MYC deregulation and EBV infection, and more recently, mutations in JAK/STAT, MAP kinase, and NOTCH pathway genes have been implicated in disease pathogenesis. The phenotypic spectrum of post-transplant (PT)-PBLs is not well characterized and data on underlying genetic alterations are limited. Hence, we performed comprehensive histopathologic and immunophenotypic evaluation and targeted sequencing of 18 samples from 11 patients (8 males, 3 females, age range 12-76 years) with PT-PBL; 8 de novo and 3 preceded by other types of PTLDs. PT-PBLs displayed morphologic and immunophenotypic heterogeneity and some features overlapped those of plasmablastic myeloma. Six (55%) cases were EBV+ and 5 (45%) showed MYC rearrangement by fluorescence in situ hybridization. Recurrent mutations in epigenetic regulators (KMT2/MLL family, TET2) and DNA damage repair and response (TP53, mismatch repair genes, FANCA, ATRX), MAP kinase (KRAS, NRAS, HRAS, BRAF), JAK/STAT (STAT3, STAT6, SOCS1), NOTCH (NOTCH1, NOTCH3, SPEN), and immune surveillance (FAS, CD58) pathway genes were observed, with EBV+ and EBV- cases exhibiting similarities and differences in their mutational profiles. Clinical outcomes also varied, with survival ranging from 0-15.9 years postdiagnosis. Besides uncovering the biological heterogeneity of PT-PBL, our study highlights similarities and distinctions between PT-PBLs and PBLs occurring in other settings and reveals potentially targetable oncogenic pathways in disease subsets.

Generation of pralatrexate resistant T-cell lymphoma lines reveals two patterns of acquired drug resistance that is overcome with epigenetic modifiers.

While pralatrexate (PDX) has been successfully developed for the treatment of T-cell lymphoma, the mechanistic basis for its T-cell selectivity and acquired resistance remains elusive. In an effort to potentially identify synergistic combinations that might circumnavigate or delay acquired PDX resistance, we generated resistant cells lines over a broad concentration range. PDX-resistant cell lines H9-12 and H9-200 were developed, each exhibiting an IC50 of 35 and over 1000 nM, respectively. These lines were established in vitro from parental H9 cells. Expression analysis of the proteins known to be important determinants of antifolate pharmacology revealed increase expression of dihydrofolate reductase (DHFR) due to gene amplification, and reduced folate carrier1 downregulation, as the putative mechanisms of resistance in H9-12 and H9-200 cells. Cross resistance was only seen with methotrexate but not with romidepsin, azacitidine (AZA), decitabine, gemcitabine, doxorubicin, or bortezomib. Resistance to PDX was reversed by pretreatment with hypomethylating agents in a concentration-dependent fashion. Comparison of gene expression profiles of parental and resistant cell lines confirmed markedly different patterns of gene expression, and identified the dual specificity phosphatase four (DUSP4) as one of the molecular target of PDX activity. Reduced STAT5 phosphorylation following exposure to PDX was observed in the H9 but not in the H9-12 and H9-200 cells. These data suggest that combination with hypomethylating agents could be potent, and that DUSP4 and STAT5 could represent putative biomarkers of PDX activity.

Cytogenetic analysis of 130 renal oncocytomas identify three distinct and mutually exclusive diagnostic classes of chromosome aberrations.

The cytogenetic alterations in renal oncocytoma (RO) are poorly understood. We analyzed 130 consecutive RO for karyotypic alterations. Clonal chromosome abnormalities were identified in 63 (49%) cases, which could be categorized into three classes of mutually exclusive cytogenetic categories. Class 1 (N = 20) RO had diploid karyotypes with characteristic 11q13 rearrangement in balanced translocations with 10 or more different chromosome partners in all cases. We identified recurrent translocation partners at 5q35, 6p21, 9p24, 11p13-14, and 11q23, and confirmed that CCND1 gene rearrangement at 11q13 utilizing fluorescence in situ hybridization (FISH). Class 2 RO (N = 25) exhibited hypodiploid karyotypes with loss of chromosome 1 and/or losses of Y in males and X in females in all cases. The class 3 tumors comprising of 18 cases showed diverse types of abnormalities with the involvement of two or more chromosomes exclusive of abnormalities seen in classes 1 and 2 tumors. Furthermore, karyotypically uninformative cases were subjected to FISH analysis to identify classes 1 and 2 abnormalities. In this group, we found similar frequencies of CCND1 rearrangement, loss of chromosome 1 or Y as with karyotypically abnormal cases. We validated our results against 91 tumors from the Mitelman database. Correlation of clinical data with all the three classes of ROs showed no clear evidence of overall patient survival. Our findings support the hypothesis that RO exhibit three principal cytogenetic categories, which may have different roles in initiation and/or progression. These cytogenetic markers provide a key tool in the diagnostic evaluation of RO.

Genetic and phenotypic characterization of indolent T-cell lymphoproliferative disorders of the gastrointestinal tract.

Indolent T-cell lymphoproliferative disorders of the gastrointestinal tract are rare clonal T-cell diseases that more commonly occur in the intestines and have a protracted clinical course. Different immunophenotypic subsets have been described, but the molecular pathogenesis and cell of origin of these lymphocytic proliferations is poorly understood. Hence, we performed targeted next-generation sequencing and comprehensive immunophenotypic analysis of ten indolent T-cell lymphoproliferative disorders of the gastrointestinal tract, which comprised CD4+ (n=4), CD8+ (n=4), CD4+/CD8+ (n=1) and CD4-/CD8- (n=1) cases. Genetic alterations, including recurrent mutations and novel rearrangements, were identified in 8/10 (80%) of these lymphoproliferative disorders. The CD4+, CD4+/CD8+, and CD4-/CD8- cases harbored frequent alterations of JAK-STAT pathway genes (5/6, 82%); STAT3 mutations (n=3), SOCS1 deletion (n=1) and STAT3-JAK2 rearrangement (n=1), and 4/6 (67%) had concomitant mutations in epigenetic modifier genes (TET2, DNMT3A, KMT2D). Conversely, 2/4 (50%) of the CD8+ cases exhibited structural alterations involving the 3' untranslated region of the IL2 gene. Longitudinal genetic analysis revealed stable mutational profiles in 4/5 (80%) cases and acquisition of mutations in one case was a harbinger of disease transformation. The CD4+ and CD4+/CD8+ lymphoproliferative disorders displayed heterogeneous Th1 (T-bet+), Th2 (GATA3+) or hybrid Th1/Th2 (T-bet+/GATA3+) profiles, while the majority of CD8+ disorders and the CD4-/CD8- disease showed a type-2 polarized (GATA3+) effector T-cell (Tc2) phenotype. Additionally, CD103 expression was noted in 2/4 CD8+ cases. Our findings provide insights into the pathogenetic bases of indolent T-cell lymphoproliferative disorders of the gastrointestinal tract and confirm the heterogeneous nature of these diseases. Detection of shared and distinct genetic alterations of the JAK-STAT pathway in certain immunophenotypic subsets warrants further mechanistic studies to determine whether therapeutic targeting of this signaling cascade is efficacious for a proportion of patients with these recalcitrant diseases.

Primary large B-cell lymphoma of the central nervous system with cyclin D1 expression and t(11;14) (IGH-CCND1): Diffuse large B-cell lymphoma with CCND1 rearrangement or mantle cell lymphoma?

Mantle cell lymphomas (MCLs) are the prototypic B-cell non-Hodgkin lymphomas defined by cyclin D1 gene (CCND1; or other cyclin D family gene) rearrangements. However, extremely rare cases of diffuse large B-cell lymphomas (DLBCLs) harboring CCND1 rearrangements, resulting in cyclin D1 protein expression, have also been reported. In this report, we describe an unusual primary large B-cell lymphoma of non-germinal center immunophenotype of the central nervous system (CNS) in an elderly male patient, which was negative for CD5 and SOX11, and exhibited cyclin D1 expression. Fluorescence in situ hybridization analysis detected IGH-CCND1 and BCL6 rearrangements. This case may represent the first report of a primary CNS DLBCL with IGH-CCND1 rearrangement. The clinico-pathologic features that can help differentiate primary CNS MCL from primary DLBCL of the CNS with IGH-CCND1 rearrangement are discussed.

The clinical and pathological features of plasma cell myeloma post solid organ transplantation.

Plasma cell neoplasms (PCNs), comprising plasma cell myelomas (PCMs) and plasmacytomas, which occur after solid organ transplantation, represent rare subtypes of monomorphic post-transplant lymphoproliferative disorders (M-PTLDs). Data regarding the clinical and pathological features of post-transplant (PT)-PCMs are limited. To gain a better understanding of disease biology, we performed comprehensive immunophenotypic analysis, reviewed cytogenetic analysis results and evaluated clinical outcomes of PT-PCMs diagnosed and treated at our institution. Fifteen PT-PCM (M: F - 4:1) and two PT-MGUS (two males) cases were identified. The median age of PT-PCM patients was 68 years (29-79 years) and PCMs presented at a median of 9.7 years (0.5-24.7 years) after transplantation. The PT-PCMs accounted for 11.6% of all M-PTLDs and the period prevalence was 9/3108 (0.29%), 3/1071 (0.28%), 2/1345 (0.15%) and 1/878 (0.11%) post kidney, heart, liver and lung transplantation. Lytic bone disease was observed in 1/11 (9%) patients. Marrow plasma cell infiltration ranged from 10%-70% (median 20%), with 10/15 (67%) and 5/15 (33%) cases manifesting immature and plasmablastic morphology. The immunophenotype of all cases and cytogenetic abnormalities, identified in 60% of cases, were similar to multiple myeloma (MM) of immunocompetent individuals. All PT-PCMs were EBER negative. Ten of 11 (91%) patients with active MM were treated, all with proteasome inhibitor-based therapy. Treatment response and 5-year overall survival (54.5%) was comparable to MM of immunocompetent individuals. However, the survival of patients with plasmablastic PCMs was inferior to those with immature PCMs. 0ur findings indicate PT-PCMs to be predominantly late onset PTLDs that have similar clinicopathologic characteristics as conventional MM.

Leukaemogenesis induced by an activating ß-catenin mutation in osteoblasts.

Cells of the osteoblast lineage affect the homing and the number of long-term repopulating haematopoietic stem cells, haematopoietic stem cell mobilization and lineage determination and B cell lymphopoiesis. Osteoblasts were recently implicated in pre-leukaemic conditions in mice. However, a single genetic change in osteoblasts that can induce leukaemogenesis has not been shown. Here we show that an activating mutation of ß-catenin in mouse osteoblasts alters the differentiation potential of myeloid and lymphoid progenitors leading to development of acute myeloid leukaemia with common chromosomal aberrations and cell autonomous progression. Activated ß-catenin stimulates expression of the Notch ligand jagged 1 in osteoblasts. Subsequent activation of Notch signalling in haematopoietic stem cell progenitors induces the malignant changes. Genetic or pharmacological inhibition of Notch signalling ameliorates acute myeloid leukaemia and demonstrates the pathogenic role of the Notch pathway. In 38% of patients with myelodysplastic syndromes or acute myeloid leukaemia, increased ß-catenin signalling and nuclear accumulation was identified in osteoblasts and these patients showed increased Notch signalling in haematopoietic cells. These findings demonstrate that genetic alterations in osteoblasts can induce acute myeloid leukaemia, identify molecular signals leading to this transformation and suggest a potential novel pharmacotherapeutic approach to acute myeloid leukaemia.

Role of Fluorescent In Situ Hybridization, Cholangioscopic Biopsies, and EUS-FNA in the Evaluation of Biliary Strictures.

BACKGROUND AND AIMS: Our goal was to compare the diagnostic accuracy of FISH in the detection of malignancy compared with other standard diagnostic modalities, including brush cytology and biopsy specimens over a 10-year period of prospective data collection. METHODS: We conducted a review of all consecutive biliary strictures evaluated between 2006 and 2016. Patients with a final pathologic diagnosis or conclusive follow-up were included. We evaluated the performance of FISH polysomy (CEP 3, 7, and 17) and 9p21 deletion as well as cholangioscopic biopsy (CBx) and EUS-FNA. Statistical analysis was performed with the Mann-Whitney U and Fisher's exact tests. RESULTS: Of 382 patients with indeterminate strictures, 281 met inclusion criteria. Forty-nine percent were malignant. Cytology, FISH polysomy, and FISH polysomy/9p21 showed a specificity of 99.3%. FISH polysomy/9p21 as a single modality was the most sensitive at 56% (p < 0.001). The sensitivity of FISH polysomy/9p21 and cytology was significantly higher than cytology alone at 63 versus 35% (p < 0.05). EUS-FNA for distal strictures and CBx for proximal strictures increased sensitivity from 33 to 93% (p < 0.001) and 48-76% (p = 0.05) in cytology-negative strictures. CONCLUSIONS: The high specificity of FISH polysomy/9p21 suggests that a positive result is sufficient for diagnosing malignancy in indeterminate strictures. The significantly higher sensitivity of FISH polysomy/9p21 compared to cytology supports the use of FISH in all non-diagnostic cases. Although both EUS-FNA and CBx were complimentary, our results suggest that distal strictures should be evaluated by EUS initially. Proximal strictures may be evaluated by FISH first and then by CBx if inconclusive.

Inactivating mutations of acetyltransferase genes in B-cell lymphoma.

B-cell non-Hodgkin's lymphoma comprises biologically and clinically distinct diseases the pathogenesis of which is associated with genetic lesions affecting oncogenes and tumour-suppressor genes. We report here that the two most common types--follicular lymphoma and diffuse large B-cell lymphoma--harbour frequent structural alterations inactivating CREBBP and, more rarely, EP300, two highly related histone and non-histone acetyltransferases (HATs) that act as transcriptional co-activators in multiple signalling pathways. Overall, about 39% of diffuse large B-cell lymphoma and 41% of follicular lymphoma cases display genomic deletions and/or somatic mutations that remove or inactivate the HAT coding domain of these two genes. These lesions usually affect one allele, suggesting that reduction in HAT dosage is important for lymphomagenesis. We demonstrate specific defects in acetylation-mediated inactivation of the BCL6 oncoprotein and activation of the p53 tumour suppressor. These results identify CREBBP/EP300 mutations as a major pathogenetic mechanism shared by common forms of B-cell non-Hodgkin's lymphoma, with direct implications for the use of drugs targeting acetylation/deacetylation mechanisms.

Epigenetic inactivation of TRAIL decoy receptors at 8p12-21.3 commonly deleted region confers sensitivity to Apo2L/trail-Cisplatin combination therapy in cervical cancer.

Multiple chromosomal regions are affected by deletions in cervical cancer (CC) genomes, but their consequence and target gene involvement remains unknown. Our single nucleotide polymorphism (SNP) array identified 8p copy number losses localized to an 8.4 Mb minimal deleted region (MDR) in 36% of CC. The 8p MDR was associated with tumor size, treatment outcome, and with multiple HPV infections. Genetic, epigenetic, and expression analyses of candidate genes at MDR identified promoter hypermethylation and/or inactivation of decoy receptors TNFRSF10C and TNFRSF10D in the majority of CC patients. TNFRSF10C methylation was also detected in precancerous lesions suggesting that this change is an early event in cervical tumorigenesis. We further demonstrate here that CC cell lines exhibiting downregulated expression of TNFRSF10C and/or TNFRSF10D effectively respond to TRAIL-induced apoptosis and this affect was synergistic in combination with DNA damaging chemotherapeutic drugs. We show that the CC cell lines harboring epigenetic inactivation of TRAIL decoy receptors effectively activate downstream caspases suggesting a critical role of inactivation of these genes in efficient execution of extrinsic apoptotic pathway and therapy response. Therefore, these findings shed new light on the role of genetic/epigenetic defects in TRAIL decoy receptor genes in the pathogenesis of CC and provide an opportunity to explore strategies to test decoy receptor gene inactivation as a biomarker of response to Apo2L/TRAIL-combination therapy.

c-Myc quadruplex-forming sequence Pu-27 induces extensive damage in both telomeric and nontelomeric regions of DNA.

Quadruplex-forming DNA sequences are present throughout the eukaryotic genome, including in telomeric DNA. We have shown that the c-Myc promoter quadruplex-forming sequence Pu-27 selectively kills transformed cells (Sedoris, K. C., Thomas, S. D., Clarkson, C. R., Muench, D., Islam, A., Singh, R., and Miller, D. M. (2012) Genomic c-Myc quadruplex DNA selectively kills leukemia. Mol. Cancer Ther. 11, 66-76). In this study, we show that Pu-27 induces profound DNA damage, resulting in striking chromosomal abnormalities in the form of chromatid or chromosomal breaks, radial formation, and telomeric DNA loss, which induces γ-H2AX in U937 cells. Pu-27 down-regulates telomeric shelterin proteins, DNA damage response mediators (RAD17 and RAD50), double-stranded break repair molecule 53BP1, G2 checkpoint regulators (CHK1 and CHK2), and anti-apoptosis gene survivin. Interestingly, there are no changes of DNA repair molecules H2AX, BRCA1, and the telomere maintenance gene, hTERT. ΔB-U937, where U937 cells stably transfected with deleted basic domain of TRF2 is partially sensitive to Pu-27 but exhibits no changes in expression of shelterin proteins. However, there is an up-regulation of CHK1, CHK2, H2AX, BRCA1, and survivin. Telomere dysfunction-induced foci assay revealed co-association of TRF1with γ-H2AX in ATM deficient cells, which are differentially sensitive to Pu-27 than ATM proficient cells. Alt (alternating lengthening of telomere) cells are relatively resistant to Pu-27, but there are no significant changes of telomerase activity in both Alt and non-Alt cells. Lastly, we show that this Pu-27-mediated sensitivity is p53-independent. The data therefore support two conclusions. First, Pu-27 induces DNA damage within both telomeric and nontelomeric regions of the genome. Second, Pu-27-mediated telomeric damage is due, at least in part, to compromise of the telomeric shelterin protein complex.

One in four individuals of African-American ancestry harbors a 5.5kb deletion at chromosome 11q13.1.

Cloning and sequencing of 5.5 kb deletion at chromosome 11q13.1 from the HeLa cells, tumorigenic hybrids and two fibroblast cell lines have revealed homologous recombination between AluSx and AluY resulting in the deletion of intervening sequences. Long-range PCR of the 5.5 kb sequence in 494 normal lymphocyte samples showed heterozygous deletion in 28.3% of African-American ancestry samples but only in 4.8% of Caucasian samples (p<0.0001). This observation is strengthened by the copy number variation (CNV) data of the HapMap samples which showed that this deletion occurs in 27% of YRI (Yoruba--West African) population but none in non-African populations. The HapMap analysis further identified strong linkage disequilibrium between 5 single nucleotide polymorphisms and the 5.5 kb deletion in people of African ancestry. Computational analysis of 175 kb sequence surrounding the deletion site revealed enhanced flexibility, low thermodynamic stability, high repetitiveness, and stable stem-loop/hairpin secondary structures that are hallmarks of common fragile sites.

Subtyping of renal cortical neoplasms in fine needle aspiration biopsies using a decision tree based on genomic alterations detected by fluorescence in situ hybridization.

OBJECTIVES: To improve the overall accuracy of diagnosis in needle biopsies of renal masses, especially small renal masses (SRMs), using fluorescence in situ hybridization (FISH), and to develop a renal cortical neoplasm classification decision tree based on genomic alterations detected by FISH. PATIENTS AND METHODS: Ex vivo fine needle aspiration biopsies of 122 resected renal cortical neoplasms were subjected to FISH using a series of seven-probe sets to assess gain or loss of 10 chromosomes and rearrangement of the 11q13 locus. Using specimen (nephrectomy)-histology as the 'gold standard', a genomic aberration-based decision tree was generated to classify specimens. The diagnostic potential of the decision tree was assessed by comparing the FISH-based classification and biopsy histology with specimen histology. RESULTS: Of the 114 biopsies diagnostic by either method, a higher diagnostic yield was achieved by FISH (92 and 96%) than histology alone (82 and 84%) in the 65 biopsies from SRMs (<4 cm) and 49 from larger masses, respectively. An optimized decision tree was constructed based on aberrations detected in eight chromosomes, by which the maximum concordance of classification achieved by FISH was 79%, irrespective of mass size. In SRMs, the overall sensitivity of diagnosis by FISH compared with histopathology was higher for benign oncocytoma, was similar for the chromophobe renal cell carcinoma subtype, and was lower for clear-cell and papillary subtypes. The diagnostic accuracy of classification of needle biopsy specimens (from SRMs) increased from 80% obtained by histology alone to 94% when combining histology and FISH. CONCLUSION: The present study suggests that a novel FISH assay developed by us has a role to play in assisting in the yield and accuracy of diagnosis of renal cortical neoplasms in needle biopsies in particular, and can help guide the clinical management of patients with SRMs that were non-diagnostic by histology.

PCDH10 promoter hypermethylation is frequent in most histologic subtypes of mature lymphoid malignancies and occurs early in lymphomagenesis.

PCDH10 is epigenetically inactivated in multiple tumor types; however, studies in mature lymphoid malignancies are limited. Here, we have investigated the presence of promoter hypermethylation of the PCDH10 gene in a large cohort of well-characterized subsets of lymphomas. PCDH10 promoter hypermethylation was identified by methylation-specific PCR in 57 to 100% of both primary B- and T-cell lymphoma specimens and cell lines. These findings were further validated by Sequenom Mass-array analysis. Promoter hypermethylation was also identified in 28.6% cases of reactive follicular hyperplasia, more commonly occurring in states of immune deregulation and associated with rare presence of clonal karyotypic aberrations, suggesting that PCDH10 methylation occurs early in lymphomagenesis. PCDH10 expression was down regulated via promoter hypermethylation in T- and B-cell lymphoma cell lines. The transcriptional down-regulation resulting from PCDH10 methylation could be restored by pharmacologic inhibition of DNA methyltransferases in cell lines. Both T- and B-cell lymphoma cell lines harboring methylation-mediated inactivation of PCDH10 were resistant to doxorubicin treatment, suggesting that hypermethylation of this gene might contribute to chemotherapy response.

Creation and characterization of BAC-transgenic mice with physiological overexpression of epitope-tagged RCAN1 (DSCR1).

The chromosome 21 gene RCAN1, encoding a modulator of the calcineurin (CaN) phosphatase, is a candidate gene for contributing to cognitive disability in people with Down syndrome (DS; trisomy 21). To develop a physiologically relevant model for studying the biochemistry of RCAN1 and its contribution to DS, we generated bacterial artificial chromosome-transgenic (BAC-Tg) mouse lines containing the human RCAN1 gene with a C-terminal HA-FLAG epitope tag incorporated by recombineering. The BAC-Tg was expressed at levels only moderately higher than the native Rcan1 gene: approximately 1.5-fold in RCAN1 (BAC-Tg1) and twofold in RCAN1 (BAC-Tg2). Affinity purification of the RCAN1 protein complex from brains of these mice revealed a core complex of RCAN1 with CaN, glycogen synthase kinase 3-beta (Gsk3b), and calmodulin, with substoichiometric components, including LOC73419. The BAC-Tg mice are fully viable, but long-term synaptic potentiation is impaired in proportion to BAC-Tg dosage in hippocampal brain slices from these mice. RCAN1 can act as a tumor suppressor in some systems, but we found that the RCAN1 BAC-Tg did not reduce mammary cancer growth when present at a low copy number in Tp53;WAP-Cre mice. This work establishes a useful mouse model for investigating the biochemistry and dose-dependent functions of the RCAN1 protein in vivo.

A novel curcumin-based vaginal cream Vacurin selectively eliminates apposed human cervical cancer cells.

OBJECTIVE: Human papillomavirus (HPV) infections remain a leading cause of mortality worldwide. In the U.S. strategies via screening and vaccination prevent HPV-associated cervical neoplasms, but consume immense healthcare costs. The spice component curcumin has potent anticancer and antiviral properties, which have been difficult to harness as a treatment, due to its poor systemic bioavailability. This project tests the possibility of developing a curcumin-based therapy for cervical cancer. METHODS: Using four HPV(+) cervical cancer cell lines and normal fibroblasts we first tested the selectivity and potency of curcumin in eliminating HPV(+) cells. Subsequently, we developed a curcumin-based cervical cream and tested its efficacy in eliminating apposed HPV(+) cells and also its possible side effects on the vaginal epithelium of healthy mice. RESULTS: Curcumin selectively eliminates a variety of HPV(+) cervical cancer cells (HeLa, ME-180, SiHa, and SW756), suppresses the transforming antigen E6, dramatically inhibits the expression of the pro-cancer protein epidermal growth factor receptor (EGFR), and concomitantly induces p53. Additionally, Vacurin, a uniform colloidal solution of curcumin in a clinically used amphipathic vaginal cream, eliminates apposed HeLa cells while suppressing the expression of EGFR. In mice, daily intravaginal application of Vacurin for three weeks produced no change in body weight and when the mice were sacrificed, the vaginal tract epithelium showed no Vacurin-evoked adverse effects. CONCLUSION: We have developed a curcumin-based vaginal cream, which effectively eradicates HPV(+) cancer cells and does not affect non-cancerous tissue. Our preclinical data support a novel approach for the treatment of cervical HPV infection.

Deregulated BCL6 expression recapitulates the pathogenesis of human diffuse large B cell lymphomas in mice.

Diffuse large B cell lymphomas (DLBCL) derive from germinal center (GC) B cells and display chromosomal alterations deregulating the expression of BCL6, a transcriptional repressor required for GC formation. To investigate the role of BCL6 in DLBCL pathogenesis, we have engineered mice that express BCL6 constitutively in B cells by mimicking a chromosomal translocation found in human DLBCL. These mice display increased GC formation and perturbed post-GC differentiation characterized by a decreased number of post-isotype switch plasma cells. Subsequently, these mice develop a lymphoproliferative syndrome that culminates with the development of lymphomas displaying features typical of human DLBCL. These results define the oncogenic role of BCL6 in the pathogenesis of DLBCL and provide a faithful mouse model of this common disease.

Lack of PTEN sequesters CHK1 and initiates genetic instability.

Pten-/- cells display a partially defective checkpoint in response to ionizing radiation (IR). The checkpoint defect was traced to the ability of AKT to phosphorylate CHK1 at serine 280, since a nonphosphorylated mutant of CHK1 (S280A) complemented the checkpoint defect and restored CDC25A degradation. CHK1 phosphorylation at serine 280 led to covalent binding of 1 to 2 molecules of ubiquitin and cytoplasmic CHK1 localization. Primary breast carcinomas lacking PTEN expression and having elevated AKT phosphorylation had increased cytoplasmic CHK1 and displayed aneuploidy (p <0.005). We conclude that loss of PTEN and subsequent activation of AKT impair CHK1 through phosphorylation, ubiquitination, and reduced nuclear localization to promote genomic instability in tumor cells.

Real-time PCR-based analysis of BRAF V600E mutation in low and intermediate grade lymphomas confirms frequent occurrence in hairy cell leukaemia.

Hairy cell leukaemia (HCL) is a rare type of B-cell non-Hodgkin lymphoma (B-NHL), which is not known to be associated with any characteristic recurrent karyotypic abnormality. A recent study that used massively parallel whole exome sequencing identified an activating V600E mutation in BRAF, which appeared specific for HCL. Here, we confirm the specificity of BRAF V600E for HCL among low and intermediate grade B-NHL and describe a real-time polymerase chain reaction method for detecting this mutation in cases with low tumour burden. The V600E mutation does not appear to be associated with microsatellite instability, unlike the case in colorectal cancer. Thus, in conjunction with prior data, our results suggest incorporation of BRAF V600E mutation analysis in the diagnostic workup of HCL cases. Additionally, targeting the Ras-Raf-Mek-Erk-Map kinase pathway should be investigated as a potential therapeutic strategy for patients with this disease.