Autoantibodies against HSF1 and CCDC155 as Biomarkers of Early-Stage, High-Grade Serous Ovarian Cancer.

Background: Tumor-directed circulating autoantibodies (AAb) are a well-established feature of many solid tumor types, and are often observed prior to clinical disease manifestation. As such, they may provide a good indicator of early disease development. We have conducted a pilot study to identify novel AAbs as markers of early-stage HGSOCs.Methods: A rare cohort of patients with early (FIGO stage Ia-c) HGSOCs for IgG, IgA, and IgM-mediated AAb reactivity using high-content protein arrays (containing 9,184 individual proteins). AAb reactivity against selected antigens was validated by ELISA in a second, independent cohort of individual patients.Results: A total of 184 antigens were differentially detected in early-stage HGSOC patients compared with all other patient groups assessed. Among the six most highly detected "early-stage" antigens, anti-IgA AAbs against HSF1 and anti-IgG AAbs CCDC155 (KASH5; nesprin 5) were significantly elevated in patients with early-stage malignancy. Receiver operating characteristic (ROC) analysis suggested that AAbs against HSF1 provided better detection of early-stage malignancy than CA125 alone. Combined measurement of anti-HSF1, anti-CCDC155, and CA125 also improved efficacy at higher sensitivity.Conclusions: The combined measurement of anti-HSF1, anti-CCDC155, and CA125 may be useful for early-stage HGSOC detection.Impact: This is the first study to specifically identify AAbs associated with early-stage HGSOC. The presence and high frequency of specific AAbs in early-stage cancer patients warrants a larger scale examination to define their value for early disease detection at primary diagnosis and/or recurrence. Cancer Epidemiol Biomarkers Prev; 27(2); 183-92. ©2017 AACR.

Humoral immune responses to cathepsin D and glucose-regulated protein 78 in ovarian cancer patients.

Many cancer patients develop tumor-reactive immune responses against antigens that are either expressed on the surface of tumor cells or released from them into the peripheral circulation. In this study, tumor-reactive immunoglobulins, present in the sera of ovarian cancer patients, were used to identify commonly recognized tumor-associated antigens on ovarian tumor cells. Western immunoblot analysis of cellular proteins, obtained from UL-1 ovarian tumor cell line, demonstrated several commonly recognized immunoreactive proteins. Two of these proteins (Mr 32,000 and 71,000) were selected for further investigation. Cellular proteins isolated from normal human ovarian epithelia, in a similar fashion, failed to exhibit corresponding immunoreactivity to these proteins. As an additional control, sera from normal (nontumor-bearing) individuals failed to identify these proteins on Western immunoblots. Furthermore, the absorption of the ovarian cancer patients' sera with normal ovarian epithelial tissue did not remove the reactivity of these two proteins. The Mr 32,000 and 71,000 proteins were subsequently purified by reverse-phase high-performance liquid chromatography, separated by SDS-PAGE, transferred to the polyvinylidene difluoride membrane, and digested with trypsin. These resulting tryptic fragments were separated by microbore reverse-phase high-performance liquid chromatography, and selected fragments were sequenced by mass spectrometry. This sequence analysis identified the Mr 32,000 protein as cathepsin D and the Mr 71,000 as glucose-regulated protein 78 (member of the heat shock protein family). The identities of cathepsin D and glucose-regulated protein 78 were confirmed by Western blot analysis. Additionally, the presence of cathepsin D was demonstrated in association with immune complexes in vivo. Currently, the common antigenic epitopes of these proteins are being defined.

Serial serum CA 125 measurements for evaluation of recurrence in patients with endometrial carcinoma.

OBJECTIVE: To evaluate the usefulness of serum assays for CA 125 to detect recurrent endometrial carcinoma. METHODS: Two hundred sixty-six patients were studied with 1101 post-treatment assays. Patients were categorized as low, medium, or high risk based on surgical-pathologic findings. CA 125 values were analyzed with respect to each patient's disease status. RESULTS: Serial CA 125 levels were elevated (greater than 35 U/mL) in 19 of 33 patients (58%) with recurrent disease. Among 236 surgically treated patients, 97 (41.1%), 42 (17.8%), and 97 (41.1%) were considered low, medium, and high risk, respectively. None of the low-risk and only two (4.7%) of the medium-risk patients developed recurrent disease. One of the latter patients was detected based on an elevated CA 125 level alone. Twenty-seven (27.8%) of the high-risk patients developed recurrent disease, 23 of whom had elevated pre-treatment CA 125. Fifteen of 16 (94%) with recurrent disease had an elevated CA 125 level. Nine of 12 patients with papillary serous carcinoma experienced recurrence; eight of these nine had elevated CA 125 levels at diagnosis and recurrence, in contrast to only one patient with a normal pre-treatment level (P = .018). False elevations were noted in 13 patients, 12 of whom had received radiation therapy. CONCLUSIONS: CA 125, if elevated at diagnosis of endometrial carcinoma, is an important marker for recurrent disease. The use of serial CA 125 assays is most beneficial in diagnosing recurrence in a high-risk population, including patients with papillary serous carcinomas. False elevations may occur following radiation therapy.

PDGF BB induces VEGF secretion in ovarian cancer.

We identified the platelet derived growth factor receptor (PDGFR) as a potential target in epithelial ovarian carcinoma (EOC). This led us to test whether inhibition of the PDGFR affects ovarian cancer cell proliferation and survival and regulates other processes critical to tumor growth and metastasis. We postulated that there is a correlation between the PDGF-PDGFR axis and the secretion of VEGF in EOC. VEGF secretion in ovarian tumors, cancer cells, serum and ascites fluid was measured by IHC, Western Blot and ELISA. We found increased VEGF expression and secretion in most ovarian tumors (by IHC), in EOC malignant ascites and in the conditioned media of primary ovarian cancer cells (quantified by ELISA). In malignant ascites, the levels of secreted PDGF BB and VEGF were strongly correlated (Pearson coefficient of correlation R = 0.728), suggesting that the two pathways interconnect. In PDGFR expressing immortalized ovarian cancer cells, PDGF potently induced VEGF secretion, while imatinib mesylate (Gleevec), a partially selective PDGFR inhibitor, reduced PDGF stimulated VEGF production to basal state. In ovarian cancer cells overexpressing constitutively active Akt, imatinib inhibited partially VEGF secretion, suggesting that the PI3K/Akt pathway is implicated in PDGF-stimulated VEGF secretion. In summary, these results suggest a correlation between the PDGF and VEGF networks in ovarian cancer cells and tumors. The effects of imatinib on VEGF secretion in tumor cells may affect the tumor microenvironment in a manner detrimental to tumor progression.

Significance of some tumor markers in differential diagnosis of ovarian tumor.

The levels of CA-125, CA 72-4 and CEA were evaluated in serum of patients with various histological types and clinical stages of ovarian carcinoma and of benign ovarian tumor. An increased CA-125 was found in 8% patients with benign ovarian tumor. The antigens CA 72-4 and CEA exhibit values below the cut-off limit. CA-125 value was significantly elevated in patients with serous and CA 72-4 with ovarian mucinous carcinoma. An increase of CA-125 was found in 81% of patients with serous, 60% with endometrioid and 30% with ovarian mucinous carcinoma. An increase of CA 72-4 was found in 76% of patients with mucinous, 54% with serous and 45% with ovarian endometrioid carcinoma. Insignificant rise of CEA value was found in 8% of patients with serous, 10% with endometrioid and 15% with ovarian mucinous carcinoma. The frequency of increased concentration of antigens level showed a trend to significant increase and a correlation with the clinical stage of disease. The observations allow to conclude that the determination of CA 72-4 in the serum may be useful in differentiation diagnostics of benign and malignant ovarian tumors. The combined determination of CA-125 and CA 72-4 is useful in differentiation of histological types of ovarian tumors and their clinical stage.