A spontaneous ovarian teratoma in an FVB/n female mouse: Case report and literature review.

Background: Teratomas are rare types of germ cell neoplasms composed of various differentiated or undifferentiated tissues. Case Description: A 25-week-old female control FVB /n mouse in a 4-week toxicity study presented abdominal distension and poor body condition. It was euthanized, and the necropsy examination revealed a large mass connected to the tip of the right uterine horn, occupying the entire abdominal cavity. Microscopically, this mass showed areas of epidermal differentiation, with laminated keratin and sebaceous glands, differentiation into respiratory and digestive epithelium, cartilage, bone, and extensive areas of differentiation into the nervous tissue, being classified as an ovarian teratoma. Conclusion: As far as authors know, the occurrence of ovarian teratomas in the FVB/n mouse strain has never been previously described.

Appraising Animal Models of Prostate Cancer for Translational Research: Future Directions.

The growing incidence of prostate cancer has prompted a great investment in basic biology and translational studies to develop new therapies. Multiple animal models have been established to study etiological factors, cancer-preventive strategies and the molecular determinants of aggressiveness and metastases. The rat model of prostate cancer induced by chemical carcinogen N-methyl-N-nitrosourea (MNU) and testosterone exposure has become an important tool to study prostatic carcinogenesis and chemopreventive approaches. Over prolonged treatment, this model develops prostatic lesions that closely mimic those observed in human patients. By modifying the experimental conditions, different research groups have been able to induce a vast spectrum of lesions, ranging from early prostatic intraepithelial neoplasia to metastatic cancer. These carefully tuned experimental settings allowed researchers to test lifestyle interventions, and different pharmacological and chemopreventive strategies. However, this model's great flexibility requires careful planning to ensure that the experimental conditions are adequate to obtain the spectrum of lesions intended. The present review addresses such issues, highlighting the value of the rat prostate cancer model and the multiple challenges and opportunities it offers to researchers worldwide.

The Red Seaweed Grateloupia turuturu Prevents Epidermal Dysplasia in HPV16-Transgenic Mice.

The role of dietary profiles in promoting or reducing the risk of multiple types of cancer is increasingly clear, driving the search for balanced foods and nutraceuticals. The red seaweed Grateloupia turuturu has been used as human food showing a balanced nutritional profile. This study aims to test in vivo chemopreventive effects of G. turuturu against cutaneous pre-malignant lesions in transgenic mice for the human papillomavirus type 16 (HPV16). Forty-four female HPV+/- or HPV-/- mice received a standard diet or were supplemented with 10% G. turuturu for 22 consecutive days. Cutaneous lesions (ear and chest skin) were identified histologically. Complementarily, the weights and histology of internal organs as well as blood biochemical and DNA integrity parameters were also assessed. G. turuturu consistently reduced the incidence of epidermal dysplasia induced by HPV16 on both cutaneous sites. Moreover, biochemical, DNA integrity and histological analyses confirmed G. turuturu edibility as no signs of toxicity were found. Dietary supplementation with G. turuturu is an effective and safe chemopreventive strategy in this model.

Towards Drug Repurposing in Cancer Cachexia: Potential Targets and Candidates.

As a multifactorial and multiorgan syndrome, cancer cachexia is associated with decreased tolerance to antitumor treatments and increased morbidity and mortality rates. The current approaches for the treatment of this syndrome are not always effective and well established. Drug repurposing or repositioning consists of the investigation of pharmacological components that are already available or in clinical trials for certain diseases and explores if they can be used for new indications. Its advantages comparing to de novo drugs development are the reduced amount of time spent and costs. In this paper, we selected drugs already available or in clinical trials for non-cachexia indications and that are related to the pathways and molecular components involved in the different phenotypes of cancer cachexia syndrome. Thus, we introduce known drugs as possible candidates for drug repurposing in the treatment of cancer-induced cachexia.

Regulation of CEACAM5 and Therapeutic Efficacy of an Anti-CEACAM5-SN38 Antibody-drug Conjugate in Neuroendocrine Prostate Cancer.

PURPOSE: Neuroendocrine prostate cancer (NEPC) is an aggressive form of castration-resistant prostate cancer (CRPC) for which effective therapies are lacking. We previously identified carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) as a promising NEPC cell surface antigen. Here we investigated the scope of CEACAM5 expression in end-stage prostate cancer, the basis for CEACAM5 enrichment in NEPC, and the therapeutic potential of the CEACAM5 antibody-drug conjugate labetuzumab govitecan in prostate cancer. EXPERIMENTAL DESIGN: The expression of CEACAM5 and other clinically relevant antigens was characterized by multiplex immunofluorescence of a tissue microarray comprising metastatic tumors from 34 lethal metastatic CRPC (mCRPC) cases. A genetically defined neuroendocrine transdifferentiation assay of prostate cancer was developed to evaluate mechanisms of CEACAM5 regulation in NEPC. The specificity and efficacy of labetuzumab govitecan was determined in CEACAM5+ prostate cancer cell lines and patient-derived xenografts models. RESULTS: CEACAM5 expression was enriched in NEPC compared with other mCRPC subtypes and minimally overlapped with prostate-specific membrane antigen, prostate stem cell antigen, and trophoblast cell surface antigen 2 expression. We focused on a correlation between the expression of the pioneer transcription factor ASCL1 and CEACAM5 to determine that ASCL1 can drive neuroendocrine reprogramming of prostate cancer which is associated with increased chromatin accessibility of the CEACAM5 core promoter and CEACAM5 expression. Labetuzumab govitecan induced DNA damage in CEACAM5+ prostate cancer cell lines and marked antitumor responses in CEACAM5+ CRPC xenograft models including chemotherapy-resistant NEPC. CONCLUSIONS: Our findings provide insights into the scope and regulation of CEACAM5 expression in prostate cancer and strong support for clinical studies of labetuzumab govitecan for NEPC.

Molecular profiling stratifies diverse phenotypes of treatment-refractory metastatic castration-resistant prostate cancer.

Metastatic castration-resistant prostate cancer (mCRPC) is a heterogeneous disease with diverse drivers of disease progression and mechanisms of therapeutic resistance. We conducted deep phenotypic characterization of CRPC metastases and patient-derived xenograft (PDX) lines using whole genome RNA sequencing, gene set enrichment analysis and immunohistochemistry. Our analyses revealed five mCRPC phenotypes based on the expression of well-characterized androgen receptor (AR) or neuroendocrine (NE) genes: (i) AR-high tumors (ARPC), (ii) AR-low tumors (ARLPC), (iii) amphicrine tumors composed of cells co-expressing AR and NE genes (AMPC), (iv) double-negative tumors (i.e. AR-/NE-; DNPC) and (v) tumors with small cell or NE gene expression without AR activity (SCNPC). RE1-silencing transcription factor (REST) activity, which suppresses NE gene expression, was lost in AMPC and SCNPC PDX models. However, knockdown of REST in cell lines revealed that attenuated REST activity drives the AMPC phenotype but is not sufficient for SCNPC conversion. We also identified a subtype of DNPC tumors with squamous differentiation and generated an encompassing 26-gene transcriptional signature that distinguished the five mCRPC phenotypes. Together, our data highlight the central role of AR and REST in classifying treatment-resistant mCRPC phenotypes. These molecular classifications could potentially guide future therapeutic studies and clinical trial design.

Curcumin and Rutin Down-regulate Cyclooxygenase-2 and Reduce Tumor-associated Inflammation in HPV16-Transgenic Mice.

AIM: Cyclo-oxygenase-2 (COX2) plays a prominent role in carcinogenesis. This study addresses the effects of two nutraceutical compounds on the expression of COX2 and tumor-associated inflammation in human papillomavirus type 16 (HPV16)-transgenic mice. MATERIALS AND METHODS: Six-week-old FVB/n mice were supplemented with rutin or curcumin for 24 weeks: HPV16-/- no treatment, n=12; HPV16+/- no treatment, n=13; HPV16+/- rutin, n=12; HPV16+/- curcumin, n=13. HPV16-induced skin lesions and their inflammatory infiltrates were studied histologically. COX2 expression was assessed immunohistochemically. RESULTS: Rutin reduced COX2 expression in the dermis (immunostaining score 7.83 versus 11.25 in untreated HPV16-transgenic mice) and epidermis (4.5 versus 10.0). Curcumin led to dermal and epidermal scores of 10.5 and 4.5. Both compounds reduced leukocytic infiltration, but neither prevented epidermal dysplasia. CONCLUSION: COX2 expression in HPV16-induced lesions may be modulated by nutraceuticals, reducing tumor-associated inflammation. However, this was not sufficient to block carcinogenesis, calling for additional studies focused on combination therapies.

Regulation of miRNA-146a and miRNA-150 Levels by Celecoxib in Premalignant Lesions of K14-HPV16 Mice.

BACKGROUND/AIM: Human papillomavirus type 16 (HPV16) induces various types of cancer in several locations. Microenvironmental microRNAs (miRNAs) such as miRNA-146a and miRNA-150 regulate cancer-associated inflammation and are involved in HPV-induced carcinogenesis. We studied the effects of celecoxib on the expression of these two miRNAs in HPV16-induced lesions. MATERIALS AND METHODS: Female transgenic (HPV16+/-) and wild-type (HPV16-/-) mice were administered 75 mg/kg/day celecoxib orally (treatment groups) or placebo (control groups) for four weeks. Skin samples were classified histologically, or used for miRNA analysis by quantitative real-time PCR. RESULTS: HPV16+/- mice showed higher miRNA-146a and miRNA-150 expression levels compared to wild-type animals. Celecoxib further increased miRNA-150 (p<0.05) and miRNA-146a levels in treated animals. Celecoxib-treated HPV16+/- animals also showed reduced incidence of epidermal dysplasia and reduced inflammation, compared to untreated mice. CONCLUSION: In this model, celecoxib may be able to regulate tumour-associated inflammation, through mechanisms involving the regulation of miRNA-146a and miRNA-150.

Celecoxib promotes degranulation of CD8(+) T cells in HPV-induced lesions of K14-HPV16 transgenic mice.

AIMS: Human papillomavirus (HPV) is a known biologic carcinogen which is commonly transmitted through sexual intercourse. CD8(+) T cells are known effectors against tumour cells and an important prognostic marker in HPV-induced cancers. COX-2 inhibitors enhance CD8(+) T cell activity against some cancers. In this work, we sought to study the presence and activation of CD8(+) T lymphocytes in lesions from K14-HPV16 transgenic mice and the immunomodulatory effect of celecoxib (CXB) over these cells. MAIN METHODS: Skin samples of CXB-treated and untreated HPV16(-/-) and HPV16(+/-) mice were enzymatically digested and analysed by flow cytometry to assess CD8(+) and CD8(+)CD107a(+) T cell infiltrates. Matched skin samples were classified histologically. KEY FINDINGS: HPV16(+/-) mice presented higher CD8(+) T cell infiltration than HPV16(-/-) animals (P<0.001). Older HPV16(+/-) animals showed epidermal dysplasia and increased percentages of CD8(+)CD107a(+) T cells compared with younger animals with hyperplasia (P<0.001), validating this model for testing the effects of celecoxib on CD8(+) T cells. CXB-treated HPV16(+/-) mice showed higher percentages of CD8(+)CD107a(+) T cells compared with untreated HPV16(+/-) animals (P<0.01), but no differences were observed concerning the progression of epidermal lesions. SIGNIFICANCE: These findings indicate that celecoxib enhances the degranulation of CD8(+) T cells on HPV16-induced lesions, suggesting the potential clinical use of COX-2 inhibitors. Additionally, this study demonstrates the usefulness of the K14-HPV16 mouse model for testing therapeutic immunomodulatory approaches.

The NFκB Signaling Pathway in Papillomavirus-induced Lesions: Friend or Foe?

Papillomaviruses induce a range of benign and malignant lesions in their hosts, including cervical cancer, that is associated with high-risk human papillomavirus (HPV) types. The nuclear factor kappa-light-chain-enhancer of activated B-cells (NFκB) plays a pivotal role in HPV-infected cells, and its expression and activity are modulated by several viral oncoproteins. NFκB modulation seems to first facilitate viral persistence and immune evasion, and later to drive tumour progression, but the many conflicting results and the complexity of its signaling networks require great prudence while interpreting the role of NFκB in papillomaviral lesions. Accordingly, the pharmacological targeting of the NFκB pathway in HPV-induced lesions is a complex and currently unmet challenge. This review deals with recent findings concerning NFκB activation in HPV-infected cells, its role in viral persistence, cell transformation and tumour progression, and with current efforts to target this pathway for cancer prevention and therapy.

The N-nitrosodiethylamine mouse model: sketching a timeline of evolution of chemically-induced hepatic lesions.

BACKGROUND/AIM: Hepatocellular carcinoma (HCC) is a frequent and aggressive malignancy associated with multiple environmental risk factors. The chemically-induced mouse model of diethylnitrosamine (DEN) provides useful insight into liver carcinogenesis, namely HCC. This work aimed to study the multistep process of hepato-carcinogenesis, providing a systematic framework for animal studies on this subject. MATERIALS AND METHODS: Male ICR mice were divided into six control and six DEN-exposed groups. Saline solution and DEN were injected intra-peritoneally, respectively, for eight consecutive weeks. Two groups (DEN vs. control) were euthanized at 8, 15, 22, 29, 36 and 40 weeks after the first administration. RESULTS: Hydropic degeneration, necrosis and apoptosis were acutely induced at eight weeks and onwards. Hyperplastic foci occurred at 29 to 40 weeks along with diffuse dysplastic areas and hepatocellular adenoma. Peliosis hepatis were also identified at 36 and 40 weeks. HCC were only noted at 40 weeks, showing characteristic histological features of malignancy. CONCLUSION: Results allowed sketching of a timeline of evolution of DEN-induced hepatic lesions in mice, from initial lesions to malignant neoplasms.

Limited role of secreted aspartyl proteinases Sap1 to Sap6 in Candida albicans virulence and host immune response in murine hematogenously disseminated candidiasis.

Candida albicans secreted aspartyl proteinases (Saps) are considered virulence-associated factors. Several members of the Sap family were claimed to play a significant role in the progression of candidiasis established by the hematogenous route. This assumption was based on the observed attenuated virulence of sap-null mutant strains. However, the exclusive contribution of SAP genes to their attenuated phenotype was not unequivocally confirmed, as the Ura status of these mutant strains could also have contributed to the attenuation. In this study, we have reassessed the importance of SAP1 to SAP6 in a murine model of hematogenously disseminated candidiasis using sap-null mutant strains not affected in their URA3 gene expression and compared their virulence phenotypes with those of Ura-blaster sap mutants. The median survival time of BALB/c mice intravenously infected with a mutant strain lacking SAP1 to SAP3 was equivalent to that of mice infected with wild-type strain SC5314, while those infected with mutant strains lacking SAP5 showed slightly extended survival times. Nevertheless, no differences could be observed between the wild type and a Δsap456 mutant in their abilities to invade mouse kidneys. Likewise, a deficiency in SAP4 to SAP6 had no noticeable impact on the immune response elicited in the spleens and kidneys of C. albicans-infected mice. These results contrast with the behavior of equivalent Ura-blaster mutants, which presented a significant reduction in virulence. Our results suggest that Sap1 to Sap6 do not play a significant role in C. albicans virulence in a murine model of hematogenously disseminated candidiasis and that, in this model, Sap1 to Sap3 are not necessary for successful C. albicans infection.