Ovarian cancer is the deadliest gynecologic cancer due predominantly to late diagnosis. Early detection of ovarian cancer can increase 5-year survival rates from 40% up to 92%, yet no reliable early ...detection techniques exist. Multiphoton microscopy (MPM) is a relatively new imaging technique sensitive to endogenous fluorophores, which has tremendous potential for clinical diagnosis, though it is limited in its application to the ovaries. Wide-field fluorescence imaging (WFI) has been proposed as a complementary technique to MPM, as it offers high-resolution imagery of the entire organ and can be tailored to target specific biomarkers that are not captured by MPM imaging. We applied texture analysis to MPM images of a mouse model of ovarian cancer. We also conducted WFI targeting the folate receptor and matrix metalloproteinases. We find that texture analysis of MPM images of the ovary can differentiate between genotypes, which is a proxy for disease, with high statistical significance (p < 0.001). The wide-field fluorescence signal also changes significantly between genotypes (p < 0.01). We use the features to classify multiple tissue groups to over 80% accuracy. These results suggest that MPM and WFI are promising techniques for the early detection of ovarian cancer.
Approximately one out of every ten cases of epithelial ovarian cancer (EOC) is inherited. The majority of inherited cases of EOC result from mutations in the breast cancer associated gene 1 (BRCA1). ...In addition to mutation of BRCA1, mutation of the p53 gene is often found in patients with inherited breast and ovarian cancer syndrome.
We investigated the role of loss of function of BRCA1 and p53 in ovarian cancer development using mouse models with conditionally expressed alleles of Brca1 and/or p53. Our results show that ovary-specific Cre-recombinase-mediated conditional inactivation of both Brca1(LoxP/LoxP) and p53(LoxP/LoxP) resulted in ovarian or reproductive tract tumor formation in 54% of mice, whereas conditional inactivation of either allele alone infrequently resulted in tumors (< or =5% of mice). In mice with conditionally inactivated Brca1(LoxP/LoxP) and p53(LoxP/LoxP), ovarian tumors arose after long latency with the majority exhibiting histological features consistent with high grade leiomyosarcomas lacking expression of epithelial, follicular or lymphocyte markers. In addition, tumors with conditional inactivation of both Brca1(LoxP/LoxP) and p53(LoxP/LoxP) exhibited greater genomic instability compared to an ovarian tumor with inactivation of only p53(LoxP/LoxP).
Although conditional inactivation of both Brca1 and p53 results in ovarian tumorigenesis, our results suggest that additional genetic alterations or alternative methods for targeting epithelial cells of the ovary or fallopian tube for conditional inactivation of Brca1 and p53 are required for the development of a mouse model of Brca1-associated inherited EOC.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Basal-like breast cancers (BLBC) are characterized by defects in homologous recombination (HR), deficient mitotic checkpoint, and high-proliferation activity. Here, we discover CIP2A as a candidate ...driver of BLBC. CIP2A was essential for DNA damage-induced initiation of mouse BLBC-like mammary tumors and for survival of HR-defective BLBC cells. CIP2A was dispensable for normal mammary gland development and for unperturbed mitosis, but selectively essential for mitotic progression of DNA damaged cells. A direct interaction between CIP2A and a DNA repair scaffold protein TopBP1 was identified, and CIP2A inhibition resulted in enhanced DNA damage-induced TopBP1 and RAD51 recruitment to chromatin in mammary epithelial cells. In addition to its role in tumor initiation, and survival of BRCA-deficient cells, CIP2A also drove proliferative MYC and E2F1 signaling in basal-like triple-negative breast cancer (BL-TNBC) cells. Clinically, high CIP2A expression was associated with poor patient prognosis in BL-TNBCs but not in other breast cancer subtypes. Small-molecule reactivators of PP2A (SMAP) inhibited CIP2A transcription, phenocopied the CIP2A-deficient DNA damage response (DDR), and inhibited growth of patient-derived BLBC xenograft. In summary, these results demonstrate that CIP2A directly interacts with TopBP1 and coordinates DNA damage-induced mitotic checkpoint and proliferation, thereby driving BLBC initiation and progression. SMAPs could serve as a surrogate therapeutic strategy to inhibit the oncogenic activity of CIP2A in BLBCs. SIGNIFICANCE: These results identify CIP2A as a nongenetic driver and therapeutic target in basal-like breast cancer that regulates DNA damage-induced G
-M checkpoint and proliferative signaling.
The mammalian target of rapamycin (mTOR) is thought to play a critical role in regulating cell growth, cell cycle progression, and tumorigenesis. Because the AKT-mTOR pathway is frequently ...hyperactivated in ovarian cancer, we hypothesized that the mTOR inhibitor RAD001 (Everolimus) would inhibit ovarian tumorigenesis in transgenic mice that spontaneously develop ovarian carcinomas. We used TgMISIIR-TAg transgenic mice, which develop bilateral ovarian serous adenocarcinomas accompanied by ascites and peritoneal dissemination. Fifty-eight female TgMISIIR-TAg mice were treated with 5 mg/kg RAD001 or placebo twice weekly from 5 to 20 weeks of age. To monitor tumor development, mice were examined biweekly using magnetic resonance microimaging. In vivo effects of RAD001 on Akt-mTOR signaling, tumor cell proliferation, and blood vessel area were analyzed by immunohistochemistry and Western blot analysis. RAD001 treatment markedly delayed tumor development. Tumor burden was reduced by approximately 84%. In addition, ascites formation, together with peritoneal dissemination, was detected in only 21% of RAD001-treated mice compared with 74% in placebo-treated animals. Approximately 30% of RAD001-treated mice developed early ovarian carcinoma confined within the ovary, whereas all placebo-treated mice developed advanced ovarian carcinoma. Treatment with RAD001 diminished the expression of vascular endothelial growth factor in tumor-derived cell lines and inhibited angiogenesis in vivo. RAD001 also attenuated the expression of matrix metalloproteinase-2 and inhibited the invasiveness of tumor-derived cells. Taken together, these preclinical findings suggest that mTOR inhibition, alone or in combination with other molecularly targeted drugs, could represent a promising chemopreventive strategy in women at high familial risk of ovarian cancer.
•Development of machine-learning algorithm for objective classification of TIL with QuPath.•Standardized methodology for TIL assessment considering tumor microenvironment.•Independent prognostic ...value of TIL in HPV positive and negative HNSCC.
The prognostic and predictive significance of pathologist-read tumor infiltrating lymphocytes (TILs) in head and neck cancers have been demonstrated through multiple studies over the years. TILs have not been broadly adopted clinically, perhaps due to substantial inter-observer variability. In this study, we developed a machine-based algorithm for TIL evaluation in head and neck cancers and validated its prognostic value in independent cohorts.
A network classifier called NN3-17 was trained to identify and calculate tumor cells, lymphocytes, fibroblasts and “other” cells on hematoxylin-eosin stained sections using the QuPath software. These measurements were used to construct three predefined TIL variables. A retrospective collection of 154 head and neck squamous cell cancer cases was used as the discovery set to identify optimal association of TIL variables and survival. Two independent cohorts of 234 cases were used for validation.
We found that electronic TIL variables were associated with favorable prognosis in both the HPV-positive and -negative cases. After adjusting for clinicopathologic factors, Cox regression analysis demonstrated that electronic total TILs% (p = 0.025) in the HPV-positive and electronic stromal TILs% (p < 0.001) in the HPV-negative population were independent markers of disease specific outcomes (disease free survival).
Neural network TIL variables demonstrated independent prognostic value in validation cohorts of HPV-positive and HPV-negative head and neck cancers. These objective variables can be calculated by an open-source software and could be considered for testing in a prospective setting to assess potential clinical implications.
Pharmacological inhibition of PARP is a promising approach in treating high grade serous ovarian carcinoma (HGSOC). PARP inhibitors (PARPi) are most active in patients with defects in DNA damage ...repair (DDR) mechanisms, such as alterations in expression/function of DNA repair and homologous recombination (HR) genes/proteins, including BRCA1 and BRCA2. Benefit of PARPi could be extended towards HR-proficient patients by combining PARPi with agents that functionally abrogate HR. An attractive molecular target for this purpose is heat shock protein 90 (HSP90), which mediates the maturation and stability of several key proteins required for DDR. Here, we tested the hypothesis that targeted inhibition of HSP90 with a small-molecule inhibitor ganetespib would sensitize non-BRCA mutant ovarian carcinoma (OC) cells to PARP inhibition by talazoparib. We used commercially available cell lines, along with several novel HGSOC OC cell lines established in our laboratory. Ganetespib treatment destabilized HSP90 client proteins involved in DNA damage response and cell cycle checkpoint, and disrupted γ-irradiation-induced DNA repair. The effects of the combination of ganetespib and talazoparib on OC cell viability and survival were also analyzed, and among the non-BRCA mutant cell lines analyzed, the combination was synergistic in several cell lines (OVCAR-3, OC-1, OC-16). Together, our data suggest that ganetespib-mediated inhibition of HSP90 effectively disrupts critical DDR pathway proteins and may sensitize OC cells without 'BRCAness' to PARPi. From a clinical perspective, this suggests that HSP90 inhibition has the potential to sensitize some HGSOC patients without HR pathway alterations to PARPi, and potentially other DNA-damage inducing agents.
In the past 3 years, altered expression of the HEF1/CAS-L/NEDD9 scaffolding protein has emerged as contributing to cancer metastasis in multiple cancer types. However, whereas some studies have ...identified elevated NEDD9 expression as prometastatic, other work has suggested a negative role in tumor progression. We here show that the Nedd9-null genetic background significantly limits mammary tumor initiation in the MMTV-polyoma virus middle T genetic model. Action of NEDD9 is tumor cell intrinsic, with immune cell infiltration, stroma, and angiogenesis unaffected. The majority of the late-appearing mammary tumors of MMTV-polyoma virus middle T;Nedd9(-/-) mice are characterized by depressed activation of proteins including AKT, Src, FAK, and extracellular signal-regulated kinase, emphasizing an important role of NEDD9 as a scaffolding protein for these prooncogenic proteins. Analysis of cells derived from primary Nedd9(+/+) and Nedd9(-/-) tumors showed persistently reduced FAK activation, attachment, and migration, consistent with a role for NEDD9 activation of FAK in promoting tumor aggressiveness. This study provides the first in vivo evidence of a role for NEDD9 in breast cancer progression and suggests that NEDD9 expression may provide a biomarker for tumor aggressiveness.
Ovarian cancer is the fifth-leading cause of cancer death among women. The dissemination of ovarian tumors and growth as spheroids accompanies late-stage disease. In cell culture, ovarian tumor cell ...spheroids can exhibit elevated resistance to environmental stressors, such as reactive oxygen species. Homeostatic balance of the antioxidant response is a protective mechanism that prevents anoikis, a form of programmed cell death. Signaling pathways activated by integrin receptors suppress anoikis. Rgnef (ARHGEF28/p190RhoGEF) is a guanine nucleotide exchange factor that is activated downstream of integrins. We find that Rgnef protein levels are elevated in late-stage serous ovarian cancer, high Rgnef mRNA levels are associated with decreased progression-free and overall survival, and genomic ARHGEF28 loss is associated with increased patient survival. Using transgenic and transplantable Rgnef knockout mouse models, we find that Rgnef is essential for supporting three-dimensional ovarian spheroid formation in vitro and tumor growth in mice. Using RNA-sequencing and bioinformatic analyses, we identify a conserved Rgnef-supported anti-oxidant gene signature including Gpx4, Nqo1, and Gsta4; common targets of the NF-kB transcription factor. Antioxidant treatment enhanced growth of Rgnef-knockout spheroids and Rgnef re-expression facilitated NF-κB-dependent tumorsphere survival. These studies reveal a new role for Rgnef in ovarian cancer to facilitate NF-κB-mediated gene expression protecting cells from oxidative stress.
Individual serum biomarkers are neither adequately sensitive nor specific for use in screening the general population for ovarian cancer. The purpose of this study was to develop a multiprotein ...classifier to detect the early stages of ovarian cancer, when it is most treatable.
The Olink Proseek Multiplex Oncology II panel was used to simultaneously quantify the expression levels of 92 cancer-related proteins in sera.
In the discovery phase, we generated a multiprotein classifier that included CA125, HE4, ITGAV, and SEZ6L, based on an analysis of sera from 116 women with early stage ovarian cancer and 336 age-matched healthy women. CA125 alone achieved a sensitivity of 87.9% at a specificity of 95%, while the multiprotein classifier resulted in an increased sensitivity of 91.4%, while holding the specificity fixed at 95%. The performance of the multiprotein classifier was validated in a second cohort comprised of 192 women with early stage ovarian cancer and 467 age-matched healthy women. The sensitivity at 95% specificity increased from 74.5% (CA125 alone) to 79.2% with the multiprotein classifier. In addition, the multiprotein classifier had a sensitivity of 95.1% at 98% specificity for late stage ovarian cancer samples and correctly classified 80.5% of the benign samples using the 98% specificity cutpoint.
The inclusion of the proteins HE4, ITGAV, and SEZ6L improved the sensitivity and specificity of CA125 alone for the detection of early stages of ovarian cancer in serum samples. Furthermore, we identified several proteins that may be novel biomarkers of early stage ovarian cancer.
PDF
