Soluble CD95 in the serum of patients with low and intermediate grade malignant lymphomas: absence of prognostic correlations

Fas expression is downregulated in gastric cancer

The aim of the present study was to investigate Fas expression in tumor samples from patients with gastric cancer, in order to determine the involvement of the Fas signaling pathway. The protein expression levels of Fas, caspase-8, caspase-3 and poly (adenosine diphosphate-ribose) polymerase 1 (PARP1) were examined in gastric cancer specimens and their associations with clinical pathological parameters were analyzed with immunohistochemical staining and western blot analysis. The mRNA expression was quantified with quantitative PCR and apoptosis was examined with a FACScan flow cytometer. The results demonstrated that the downregulation of Fas expression was correlated with less histological differentiation, gender (male), and increased lymph node and distant metastases (P<0.05). In the AGS established gastric cancer cell line, upregulation of the Fas signaling pathway promoted the apoptosis of gastric cancer cells by upregulating the expression of caspase-8 and caspase-3, and downregulating the expression of PARP1. The present study demonstrated that Fas was associated with gastric cancer and promoted the apoptosis of gastric cancer cells via caspase-8, caspase-3 and PARP1. These results suggested that caspase-8, caspase-3 and PARP1 may be triggers of gastric cancer, and upregulation of caspase-8 and caspase-3 expression, or inhibition of PARP1 expression may improve the therapeutic outcome in patients with gastric cancer.

Serum efficacy biomarkers for oncology

Considerable interest has emerged in serum biomarkers that can be used to evaluate early effects of cancer therapeutics. Such efficacy biomarkers are expected to become valuable both for routine clinical care and for anticancer drug development. Here, we review the literature on serum efficacy biomarkers. We discuss how data using such markers can be interpreted, particularly with regard to the issue of specificity of different markers. An important question is whether biomarker response evaluation is expected to be congruent with evaluation by traditional anatomical methods. We argue that they may not be - biomarkers are expected to provide information with regard to induction of tumor cell death that will not necessarily reflect clinical outcome.

Serum soluble Fas levels and prediction of response to platinum-based chemotherapy in epithelial ovarian cancer

Epithelial ovarian cancer (EOC) is treated mainly by platinum-based combination chemotherapy. Chemotherapy induces apoptosis in which the Fas/Fas ligand pathway is important. Serum soluble Fas (sFas) is a biomarker of this pathway and functionally inhibits Fas-/FasL-mediated apoptosis. In this study, we have investigated the role of sFas in prediction of response to chemotherapy in EOC. Thirty-five patients were recruited and their serum sFas levels were estimated by ELISA at 4 time points-preoperative (sFas1), postoperative (sFas2), midchemotherapy (sFas3) and at the end of chemotherapy (sFas4). The response to chemotherapy was documented clinically, radiologically and by CA-125 levels, based on which, 2 groups were identified: primary chemosensitive (n = 24) and primary chemoresistant (n = 11). Based on the disease status at last follow-up, 2 groups were identified: No Evidence of Disease (n = 15) and Evidence of Disease (n = 20). The primary chemoresistant tumors showed significantly higher median sFas2 levels (p = 0.033) with the sFas2/sFas1 ratio > or =1 (p = 0.001). A multivariate Cox proportional hazards regression model identified sFas2/sFas1 ratio as a significant factor for the prediction of response to platinum-based chemotherapy (p = 0.011). Receiver operating characteristic (ROC) analysis showed that at a ratio of 1.2, sFas2/sFas1 achieved a sensitivity of 82% and specificity of 100% for prediction of chemotherapeutic response. sFas2/sFas1 and sFas3/sFas1 ratio was also higher in patients with evidence of disease (p = 0.018 and p = 0.028, respectively). Progression-free survival rates in patients with sFas2/sFas1 ratio <1 exceeded those with ratio > or =1 (p = 0.004). In conclusion, serum sFas is a useful biomarker for predicting response to platinum-based chemotherapy in EOC.

Apoptotic markers in cancer

In cancer, apoptotic processes occur both spontaneously and induced by antitumor therapies. Qualitative and quantitative changes in cancer cell death along with proliferative alterations are essential determinants in the pathogenesis and progression of malignant disease and its responsiveness to therapy. Besides detecting apoptosis by invasive means in tumor tissue, apoptotic products can be quantified in the circulation. Although circulating apoptotic products usually lack organ and tumor specificity, they contribute in the assessment of disease extent or aggressiveness. The ease of drawing blood facilitates the serial measurement of circulating apoptotic markers to monitor antitumor treatment and predict early response to therapy. This review describes the features of apoptotic and necrotic cell death along with the role the balance between the rates of cell death and cell proliferation plays in the progression of malignancy. The intracellular pathways mediating apoptosis are next summarized. The focus then shifts to the apoptotic markers found in the circulation and their diagnostic, prognostic, predictive, and management utility in cancer.

Plasma Fas ligand, an inducer of apoptosis, and plasma soluble Fas, an inhibitor of apoptosis, in advanced melanoma

The transmembrane receptor Fas/APO-1, together with its protein-binding partner (Fas ligand), is a key regulator of programmed cell death and induces apoptosis when it binds Fas ligand (FasL) or soluble Fas ligand (sFasL). However, soluble Fas (sFas) blocks apoptosis by inhibiting binding between Fas and FasL or sFasL. At present, the status of sFas and sFasL in metastatic malignant melanoma remains unknown. This study sought to evaluate the relationship between plasma levels of sFas and/or sFasL and clinical response in 45 metastatic malignant melanoma patients treated by biochemotherapy. sFas and sFasL were measured by specific enzyme-linked immunosorbent assay (ELISA) tests in the sera from patients and 34 healthy donors. Overall, sFas and sFasL levels in patients were significantly higher (P < 0.0001) than in healthy donors. Before the biochemotherapy treatment the sFas level was about the same in biochemorefractory (n = 26) as in responder patients (n = 19). In contrast, the sFasL level was very high only in biochemorefractory patients. At the end of the treatment, in biochemorefractory patients the sFas level was extremely significantly increased (P < 0.0001) and a significant decrease in the plasma levels of sFasL was observed (P = 0.0002). In responder patients, no change in sFas and sFasL was detected. In conclusion, elevated levels of sFas and sFasL might be associated with poor prognosis in advanced melanoma; their possible role in the regulation of apoptosis in influencing the response to biochemotherapy should be further explored.

Circulating levels of TNF alpha and TNF receptor superfamily members in lymphoid neoplasia

We have correlated the serum levels of TNF alpha and soluble TNF receptor superfamily members with clinico-pathologic parameters in patients of Hodgkin's disease (HD, N = 26) and non-Hodgkin's lymphoma (NHLs, N = 35). HD patients had significantly higher levels of TNF alpha, sTNFRI, and sTNFRII in serum while NHL patients had significantly higher levels of sTNFRI, sTNFRII, sCD27, and sFas as compared to controls. In NHL patients the levels of sCD27 correlated directly and significantly with the high-stage disease, bone marrow involvement, lymph nodal presentation, and serum LDH levels. Similarly in NHL patients, levels of sFas also correlated directly and significantly with the presence of high stage disease. HD patients with B symptoms had significantly higher levels of sTNFRII.

Significance of Fas protein in squamous cell carcinoma of the larynx

The purpose was to elucidate the clinical significance of Fas protein in laryngeal squamous cell carcinoma (LSSC). Medical records of 30 patients who were operated for LSCC between 1991 and 1997 were reviewed, and histopathological and immunohistochemical studies of the archival tumor tissues were performed. Conventional histopathology included tumor grading, mitotic counting (MC) and status of the cervical lymph nodes. The monoclonal antibodies to Fas (DAKO M 3554) and nm23 (DAKO A0096 Lot 035) proteins were used for immunohistochemical staining. Streptavidin-Biotin, horseradish method was used. Positive staining for both Fas and nm23 was obtained in 27 (90%) tumor samples. There was no correlation between neck metastasis and Fas positivity (r = 0.126, p = 0.505 and chi2 = 0.062, p = 0.996, respectively). Fas positivity did not correlate to grade (r = 0.282, p = 0.130), tumor size or T (r = 0.0457, p = 0.810, chi2 = 0.0.018, p = 0.999) or laryngeal site of involvement (chi2 = 0.0937, p = 0.992). However, a correlation was found between Fas and MC (r = 0.482. p = 0.007). There was also a correlation between Fas and nm23 positivity (r = 0.614, p < 0.0001). Fas protein expression has no prognostic value in LSCC, because the Fas values do not correlate with grade, stage or nodal status of neck. However, 90% of LSCCs expressed Fas protein. Understanding the functional status of the Fas receptor proteins may lead to development of new therapeutic options for LSSC in the future.

The dynamics of life and death of malignant lymphocytes

Normal lymphocytes constantly receive death and survival signals. The balance between these two opposing pathways ensures lymphocyte homeostasis and prevents autoimmunity. This article focuses on the opposing functions of CD40 and Fas receptor/ligand pairs in B-cell lymphoid malignancies and Hodgkin's disease. Understanding these pathways may enhance the future design of immunotherapy against lymphoid malignancies.