Multicenter validation of cancer gene panel-based next-generation sequencing for translational research and molecular diagnostics.

The simultaneous detection of multiple somatic mutations in the context of molecular diagnostics of cancer is frequently performed by means of amplicon-based targeted next-generation sequencing (NGS). However, only few studies are available comparing multicenter testing of different NGS platforms and gene panels. Therefore, seven partner sites of the German Cancer Consortium (DKTK) performed a multicenter interlaboratory trial for targeted NGS using the same formalin-fixed, paraffin-embedded (FFPE) specimen of molecularly pre-characterized tumors (n = 15; each n = 5 cases of Breast, Lung, and Colon carcinoma) and a colorectal cancer cell line DNA dilution series. Detailed information regarding pre-characterized mutations was not disclosed to the partners. Commercially available and custom-designed cancer gene panels were used for library preparation and subsequent sequencing on several devices of two NGS different platforms. For every case, centrally extracted DNA and FFPE tissue sections for local processing were delivered to each partner site to be sequenced with the commercial gene panel and local bioinformatics. For cancer-specific panel-based sequencing, only centrally extracted DNA was analyzed at seven sequencing sites. Subsequently, local data were compiled and bioinformatics was performed centrally. We were able to demonstrate that all pre-characterized mutations were re-identified correctly, irrespective of NGS platform or gene panel used. However, locally processed FFPE tissue sections disclosed that the DNA extraction method can affect the detection of mutations with a trend in favor of magnetic bead-based DNA extraction methods. In conclusion, targeted NGS is a very robust method for simultaneous detection of various mutations in FFPE tissue specimens if certain pre-analytical conditions are carefully considered.

Targeted delivery of an ADP-ribosylating bacterial toxin into cancer cells.

The actin cytoskeleton is an attractive target for bacterial toxins. The ADP-ribosyltransferase TccC3 from the insect bacterial pathogen Photorhabdus luminescence modifies actin to force its aggregation. We intended to transport the catalytic part of this toxin preferentially into cancer cells using a toxin transporter (Protective antigen, PA) which was redirected to Epidermal Growth Factor Receptors (EGFR) or to human EGF receptors 2 (HER2), which are overexpressed in several cancer cells. Protective antigen of anthrax toxin forms a pore through which the two catalytic parts (lethal factor and edema factor) or other proteins can be transported into mammalian cells. Here, we used PA as a double mutant (N682A, D683A; mPA) which cannot bind to the two natural anthrax receptors. Each mutated monomer is fused either to EGF or to an affibody directed against the human EGF receptor 2 (HER2). We established a cellular model system composed of two cell lines representing HER2 overexpressing esophageal adenocarcinomas (EACs) and EGFR overexpressing esophageal squamous cell carcinomas (ESCCs). We studied the specificity and efficiency of the re-directed anthrax pore for transport of TccC3 toxin and established Photorhabdus luminescence TccC3 as a toxin suitable for the development of a targeted toxin selectively killing cancer cells.

Fibroblast activation protein-α, a stromal cell surface protease, shapes key features of cancer associated fibroblasts through proteome and degradome alterations.

Cancer associated fibroblasts (CAFs) constitute an abundant stromal component of most solid tumors. Fibroblast activation protein (FAP) α is a cell surface protease that is expressed by CAFs. We corroborate this expression profile by immunohistochemical analysis of colorectal cancer specimens. To better understand the tumor-contextual role of FAPα, we investigate how FAPα shapes functional and proteomic features of CAFs using loss- and gain-of function cellular model systems. FAPα activity has a strong impact on the secreted CAF proteome ("secretome"), including reduced levels of anti-angiogenic factors, elevated levels of transforming growth factor (TGF) ß, and an impact on matrix processing enzymes. Functionally, FAPα mildly induces sprout formation by human umbilical vein endothelial cells. Moreover, loss of FAPα leads to a more epithelial cellular phenotype and this effect was rescued by exogenous application of TGFß. In collagen contraction assays, FAPα induced a more contractile cellular phenotype. To characterize the proteolytic profile of FAPα, we investigated its specificity with proteome-derived peptide libraries and corroborated its preference for cleavage carboxy-terminal to proline residues. By "terminal amine labeling of substrates" (TAILS) we explored FAPα-dependent cleavage events. Although FAPα acts predominantly as an amino-dipeptidase, putative FAPα cleavage sites in collagens are present throughout the entire protein length. In contrast, putative FAPα cleavage sites in non-collagenous proteins cluster at the amino-terminus. The degradomic study highlights cell-contextual proteolysis by FAPα with distinct positional profiles. Generally, our findings link FAPα to key aspects of CAF biology and attribute an important role in tumor-stroma interaction to FAPα.

Quantitative proteomic analysis of formalin-fixed, paraffin-embedded clear cell renal cell carcinoma tissue using stable isotopic dimethylation of primary amines.

BACKGROUND: Formalin-fixed, paraffin-embedded (FFPE) tissues represent the most abundant resource of archived human specimens in pathology. Such tissue specimens are emerging as a highly valuable resource for translational proteomic studies. In quantitative proteomic analysis, reductive di-methylation of primary amines using stable isotopic formaldehyde variants is increasingly used due to its robustness and cost-effectiveness. RESULTS: In the present study we show for the first time that isotopic amine dimethylation can be used in a straightforward manner for the quantitative proteomic analysis of FFPE specimens without interference from formalin employed in the FFPE process. Isotopic amine dimethylation of FFPE specimens showed equal labeling efficiency as for cryopreserved specimens. For both FFPE and cryopreserved specimens, differential labeling of identical samples yielded highly similar ratio distributions within the expected range for dimethyl labeling. In an initial application, we profiled proteome changes in clear cell renal cell carcinoma (ccRCC) FFPE tissue specimens compared to adjacent non-malignant renal tissue. Our findings highlight increased levels of glyocolytic enzymes, annexins as well as ribosomal and proteasomal proteins. CONCLUSION: Our study establishes isotopic amine dimethylation as a versatile tool for quantitative proteomic analysis of FFPE specimens and underlines proteome alterations in ccRCC.

STAT3 expression, activity and functional consequences of STAT3 inhibition in esophageal squamous cell carcinomas and Barrett's adenocarcinomas.

Signal transducer and activator of transcription 3 (STAT3) is altered in several epithelial cancers and represents a potential therapeutic target. Here, STAT3 expression, activity and cellular functions were examined in two main histotypes of esophageal carcinomas. In situ, immunohistochemistry for STAT3 and STAT3-Tyr705 phosphorylation (P-STAT3) in esophageal squamous cell carcinomas (ESCC, n=49) and Barrett's adenocarcinomas (BAC, n=61) revealed similar STAT3 expression in ESCCs and BACs (P=0.109), but preferentially activated P-STAT3 in ESCCs (P=0.013). In vitro, strong STAT3 activation was seen by epidermal growth factor (EGF) stimulation in OE21 (ESCC) cells, whereas OE33 (BAC) cells showed constitutive weak STAT3 activation. STAT3 knockdown significantly reduced cell proliferation of OE21 (P=0.0148) and OE33 (P=0.0243) cells. Importantly, STAT3 knockdown reduced cell migration of OE33 cells by 2.5-fold in two types of migration assays (P=0.073, P=0.015), but not in OE21 cells (P=0.1079, P=0.386). Investigation of transcriptome analysis of STAT3 knockdown revealed a reduced STAT3 level associated with significant downregulation of cell cycle genes in both OE21 (P<0.0001) and OE33 (P=0.01) cells. In contrast, genes promoting cell migration (CTHRC1) were markedly upregulated in OE21 cells, whereas a gene linked to tight-junction stabilization and restricted cell motility (SHROOM2) was downregulated in OE21 but upregulated in OE33 cells. This study shows frequent, but distinct, patterns of STAT3 expression and activation in ESCCs and BACs. STAT3 knockdown reduces cell proliferation in ESCC and BAC cells, inhibits migration of BAC cells and may support cell migration of ESCC cells. Thereby, novel STAT3-regulated genes involved in ESCC and BAC cell proliferation and cell migration were identified. Thus, STAT3 may be further exploited as a potential novel therapeutic target, however, by careful distinction between the two histotypes of esophageal cancers.

Gab2 signaling in chronic myeloid leukemia cells confers resistance to multiple Bcr-Abl inhibitors.

Grb2-associated binder 2 (Gab2) serves as a critical amplifier in the signaling network of Bcr-Abl, the driver of chronic myeloid leukemia (CML). Despite the success of tyrosine kinase inhibitors (TKIs) in CML treatment, TKI resistance, caused by mutations in Bcr-Abl or aberrant activity of its network partners, remains a clinical problem. Using inducible expression and knockdown systems, we analyzed the role of Gab2 in Bcr-Abl signaling in human CML cells, especially with respect to TKI sensitivity. We show for the first time that Gab2 signaling protects CML cells from various Bcr-Abl inhibitors (imatinib, nilotinib, dasatinib and GNF-2), whereas Gab2 knockdown or haploinsufficiency leads to increased TKI sensitivity. We dissected the underlying molecular mechanism using various Gab2 mutants and kinase inhibitors and identified the Shp2/Ras/ERK and the PI3K/AKT/mTOR axes as the two critical signaling pathways. Gab2-mediated TKI resistance was associated with persistent phosphorylation of Gab2 Y452, a PI3K recruitment site, and consistent with this finding, the protective effect of Gab2 was completely abolished by the combination of dasatinib with the dual PI3K/mTOR inhibitor NVP-BEZ235. The identification of Gab2 as a novel modulator of TKI sensitivity in CML suggests that Gab2 could be exploited as a biomarker and therapeutic target in TKI-resistant disease.

[Update on Barrett esophagus and Barrett carcinoma]. / Update zum Barrett-Ösophagus und Barrett-Karzinom.

The definition of Barrett esophagus is currently under discussion. It is now suggested that a distal esophagus coated with cylinder epithelium with cardia-fundus mucosa should also be classified as Barrett esophagus because the risk of cancer is significantly increased even without histological evidence of intestinal metaplasia with goblet cells. The results of recent epidemiological investigations imply that the cancer risk of cylinder cell metaplasia and low grade intraepithelial neoplasia in Barrett esophagus has previously been overestimated. The histological detection of dysplasia still remains the best biomarker for estimation of the risk of cancer of Barrett esophagus. Exact determination of invasion depth in the mucosa, respective submucosa is now established as prognostic marker for overall survival in Patients with early carcinomas and this classification is useful for therapy decisions (endoscopic versus surgical removal). In advanced Barrett carcinoma following neoadjuvant therapy the lymph node status (ypN) is a better prognostic factor than the ypT category. In metastasized tumors therapies targeting HER2/new, EGFR or c-Met have been investigated explicitly in Barrett carcinoma only in phase I/II studies, whereby the predictive value of appropriate molecular pathology investigations is not yet reliably established.

Aurora-B protein expression is linked to initial response to taxane-based first-line chemotherapy in stage III ovarian carcinoma.

AIMS: Aurora kinases are central to cell proliferation and considered to be prognostic/predictive markers and therapeutic targets for epithelial cancers. Here, the prognostic/predictive value of Aurora-B protein expression was evaluated in patients with serous, FIGO stage III ovarian carcinomas treated with taxane- or platinum-based first-line chemotherapy (1st-CTx). METHODS: Immunohistochemistry was performed on tissue microarrays, including 80 ovarian carcinomas and 18 non-neoplastic ovaries, previously characterised for Aurora-A protein expression. None or marginal (score 0+1), moderate (score 2) and strong (score 3) Aurora-B protein expression was correlated with clinico-pathological parameters as well as recurrence-free survival (RFS) and overall survival (OS). RESULTS: While non-neoplastic ovaries were negative for Aurora-B, almost all (79/80; 99%) ovarian carcinomas exhibited Aurora-B positive tumour cells, with score 1 in 41/80 (51%), score 2 in 23/80 (29%) and score 3 in 15/80 (19%) cases. Aurora-B and Aurora-A protein expression correlated significantly (p=0.002). In optimal debulked patients, Aurora-B protein expression was associated with RFS (p=0.011, n=53) and marginally with OS (p=0.460; n=53). Moreover, Aurora-B protein expression was predictive for RFS of optimal debulked patients with taxane-based (p=0.006; n=32), but not with platinum-based (p=0.720; n=20) 1st-CTx. Aurora-B protein expression was not linked to OS in optimal debulked patients with either of the two 1st-CTx. CONCLUSIONS: Aurora-B protein expression frequently occurs in serous, FIGO stage III ovarian carcinomas, making it a 'drugable' molecular target in the majority of ovarian carcinoma patients. Moreover, Aurora-B protein expression is predictive for initial response to taxane-based 1st-CTx in optimal debulked, late stage ovarian carcinoma patients.

Bone morphogenetic protein modulator BMPER is highly expressed in malignant tumors and controls invasive cell behavior.

Bone morphogenetic proteins (BMPs) are growth factors that exert important functions in cell proliferation, migration and differentiation. Till date, multiple human tumors have been reported to display a dysregulation of several members of the BMP pathway that is associated with enhanced malignant tumor growth and metastasis. BMPER (BMP endothelial cell precursor-derived regulator) is a direct BMP modulator that is necessary for BMPs to exert their full-range signaling activity. Moreover, BMPER is expressed by endothelial cells and their progenitors, and has pro-angiogenic features in these cells. Here, we describe the expression of BMPER in human specimens of lung, colon and cervix carcinomas and cell lines derived from such carcinomas. In contrast to healthy tissues, BMPER is highly expressed upon malignant deterioration. Functionally, loss of BMPER in the lung tumor cell line A549 impairs proliferation, migration, invasion as well as tumor cell-induced endothelial cell sprout formation. In contrast, stimulation of A549 cells with exogenous BMPER had no further effect. We found that the BMPER effect may be transduced by regulation of the BMP target transcription factor inhibitor of DNA binding 1 (Id1) and matrix metalloproteinases (MMPs) 9 and 2. These facilitators of cell migration are downregulated when BMPER is absent. To prove the relevance of our in vitro results in vivo, we generated Lewis lung carcinoma cells with impaired BMPER expression and implanted them into the lungs of C57BL/6 mice. In this model, the absence of BMPER resulted in severely reduced tumor growth and tumor angiogenesis. Taken together, these data unequivocally demonstrate that the BMP modulator BMPER is highly expressed in malignant tumors and tumor growth is dependent on the presence of BMPER.

[Intraepithelial neoplasia of Barrett's esophagus: prognosis of potential malignancy]. / Intraepitheliale Neoplasie des Barrett-Ösophagus: Vorhersage des malignen Potenzials.

Adenocarcinomas of the distal esophagus mainly develop from intestinal metaplasia (Barrett's esophagus) through intermediate steps of low-grade and high-grade intraepithelial neoplasia. Histopathological examination of endoscopic biopsies constitutes the gold standard for estimating the cancer risk of a patient with Barrett's esophagus. Several prospective biomarker phase IV studies have demonstrated the predictive value of e.g. allelic loss of TP53, tetraploidy and aneuploidy as well as cyclin D1 expression. Among the relevant biomarkers from retrospective phase III studies are polysomy and specific DNA gains and losses, markers of proliferation (Mib-1) and methylation markers. As there are conflicting results in the literature and these analyses are costly, their use in routine patient care cannot yet be recommended. However, immunostaining for several markers may assist in the classification of intraepithelial neoplasia in individual difficult cases.

Intraepithelial CD8-positive T lymphocytes predict survival for patients with serous stage III ovarian carcinomas: relevance of clonal selection of T lymphocytes.

BACKGROUND: The aim of this study was to investigate the prognostic effect of tumour-infiltrating lymphocytes (TILs) in serous stage III ovarian carcinoma to determine TIL clonality and to correlate this to Her2/neu expression. METHODS: Formalin-fixed and paraffin-embedded ovarian carcinomas were examined for CD20-, CD3-, CD4- and CD8-positive lymphocytes (n=100), and for Her2/neu-positive tumour cells (n=55/100) by immunohistochemistry. Clonality analysis was carried out by T-cell receptor gamma (TCRgamma) gene rearrangements (n=93/100). Statistical analyses included experimental and clinico-pathological variables, as well as disease-free (DFS) and overall (OS) survival. RESULTS: CD20-positive B lymphocytes were present in 57.7% (stromal)/33.0% (intraepithelial) and CD3-positive T lymphocytes in 99.0% (stromal)/90.2% (intraepithelial) of ovarian carcinomas. Intraepithelial CD3-positive T lymphocytes were correlated with improved DFS in optimally debulked patients (P=0.0402). Intraepithelial CD8-positive T lymphocytes were correlated with improved OS in all optimally debulked patients (P=0.0201) and in those undergoing paclitaxel/carboplatin therapy (P=0.0092). Finally, rarified and clonal TCRgamma gene rearrangements were detected in 37 out of 93 (39.8%) and 15 out of 93 (16.1%) cases, respectively. This was marginally associated with improved DFS (P=0.0873). Despite a significant correlation of HER2/neu status and intraepithelial CD8-positive lymphocytes (P=0.0264), this was non-directional (R=-0.257; P=0.0626). CONCLUSION: Improved survival of ovarian cancer patients is related to the infiltration, clonal selection and intraepithelial persistence of T lymphocytes.

CpG-island methylation of the ER promoter in colorectal cancer: analysis of micrometastases in lymph nodes from UICC stage I and II patients.

Patients with UICC stage II colorectal cancer (CRC) have a risk of approximately 20% to develop disease recurrence after tumour resection. The presence and significance of micrometastases for locoregional recurrence in these patients lacking histopathological lymph node involvement on routine stained HE sections is undefined. Oestrogen receptor (ER) promoter methylation has earlier been identified in CRC. Therefore, we evaluated the methylation status of the ER promoter in lymph nodes from 49 patients with CRC UICC stage I and II as a molecular marker of micrometastases and predictor of local recurrence. DNA from 574 paraffin-embedded lymph nodes was isolated and treated with bisulphite. For the detection of methylated ER promoter sequences, quantitative real-time methylation-specific PCR was used. Of the 49 patients tested, 15 (31%) had ER methylation-positive lymph nodes. Thirteen of those (86%) remained disease free and two (14%) developed local recurrence. In the resected lymph nodes of 34 of the 49 patients (69%), no ER promoter methylation could be detected and none of these patients experienced a local relapse. The methylation status of the ER promoter in lymph nodes of UICC stage I and II CRC patients may be a useful marker for the identification of patients at a high risk for local recurrence.

[Aurora-a is a predictive marker for stage III epithelial ovarian cancers]. / Aurora-a ist ein prädiktiver Marker für Ovarialkarzinome des Stadiums III.

AIM: Overexpression of Aurora-A/STK15 kinase (hereafter AUKRA) is seen in a variety of epithelial cancers, such as gastrointestinal and gynaecological carcinomas. Its role as prognostic and/or predictive marker for adjuvant therapy of patients with advanced ovarian cancer is however still unclear. Therefore, the present study aimed at determining (1) the clinical value of AURKA expression (mRNA and protein) in 115 patients with ovarian carcinomas and (2) the basis of AURKA overexpression at the DNA level. METHODS: Formalin-fixed and Paraffin-embedded tissue samples (ovarian carcinoma: n=115; non-neoplastic ovaries: n=28) were processed for microdissection and quantitative RT-PCR as well as for semi-quantitative immunohistochemistry (IHC) of tissue microarrays according to standardised protocols. Fluorescence in Situ Hybridisation (FISH) was performed in a sub-set of cases (n=37) to analyse AURKA DNA copy numbers. RESULTS: The results demonstrate significantly elevated AURKA expression at the mRNA and protein level in ovarian carcinomas as compared to non-neoplastic ovaries (p < 0.0001). AURKA protein overexpression was observed in 68/107 (63.5%) of cases. For patients with stage III ovarian carcinoma having been optimally debulked and receiving adjuvant Taxane-based chemotherapy, AURKA overexpression was significantly linked to prolonged overall survival (p = 0.02). Finally AURKA overexpression was associated with increased AURKA DNA copy numbers (p = 0.01). CONCLUSION: In summary, AURKA overexpression, which is regulated at the DNA level, is a novel predictive marker for a subgroup of patients with stage III ovarian carcinomas.

Identification of occult tumor cells in node negative lymph nodes of colorectal cancer patients by cytokeratin 20 gene and protein expression.

BACKGROUND AND AIMS: Evaluation of cytokeratin 20 (CK20) specific quantitative reverse transcriptase polymerase chain reaction (QRT-PCR) and immunohistochemistry (IHC) for detection of occult tumor cells in lymph nodes of 72 patients with colorectal carcinoma (UICC stage I and II). METHODS: Serial sections of formalin-fixed, paraffin-embedded lymph nodes (mean 14.3/case) were used for microdissection, RNA isolation and QRT-PCR and for CK20 IHC using routine protocols. Results of QRT-PCR and IHC were compared and correlated to the CK20 expression pattern of the primary tumors and clinical follow-up. RESULTS: IHC revealed CK20-positive tumor cells in lymph nodes of 14.5% (10/69) and 0% (0/3) cases with a CK20-positive and CK20-negative primary tumor, respectively. CK20 mRNA was detected in the lymph nodes of 36.8% (7/19) cases by QRT-PCR with all 7 cases also expressing CK20 mRNA in the primary tumor. CK20 mRNA (QRT-PCR) and protein (IHC) detection in serial sections did not agree in 25% (5/20) of cases. A trend was seen towards a worse disease course for patients with CK20-positive lymph nodes by IHC (incidence of recurrent disease) and QRT-PCR (disease-free survival, incidence of recurrent disease). CONCLUSION: CK20-specific IHC and QRT-PCR are supportive tools to conventional histology for detection of occult tumor cells in archival tissues, with the restriction that a laborious QRT-PCR procedure is necessary to achieve appropriate specificity. A prognostic value of CK20 IHC or QRT-PCR for stratification of UICC stage I and II patients into those likely to develop recurrent disease was not evident.

C10 is a novel chemokine expressed in experimental inflammatory demyelinating disorders that promotes recruitment of macrophages to the central nervous system.

Chemokines may be important in the control of leukocytosis in inflammatory disorders of the central nervous system. We studied cerebral chemokine expression during the evolution of diverse neuroinflammatory disorders in transgenic mice with astrocyte glial fibrillary acidic protein-targeted expression of the cytokines IL-3, IL-6, or IFN-alpha and in mice with experimental autoimmune encephalomyelitis. Distinct chemokine gene expression patterns were observed in the different central nervous system inflammatory models that may determine the phenotype and perhaps the functions of the leukocytes that traffic into the brain. Notably, high expression of C10 and C10-related genes was found in the cerebellum and spinal cord of GFAP-IL3 mice with inflammatory demyelinating disease and in mice with experimental autoimmune encephalomyelitis. In both these neuroinflammatory models, C10 RNA and protein expressing cells were predominantly macrophage/microglia and foamy macrophages present within demyelinating lesions as well as in perivascular infiltrates and meninges. Intracerebroventricular injection of recombinant C10 protein promoted the recruitment of large numbers of Mac-1(+) cells and, to a much lesser extent, CD4(+) lymphocytes into the meninges, choroid plexus, ventricles, and parenchyma of the brain. Thus, C10 is a prominent chemokine expressed in the central nervous system in experimental inflammatory demyelinating disease that, we show, also acts as a potent chemotactic factor for the migration of these leukocytes to the brain.

Salivary gland protection by amifostine in high-dose radioiodine therapy of differentiated thyroid cancer.

BACKGROUND: Salivary gland impairment following high-dose radioiodine treatment is a well-recognized side effect, in general caused by free radicals. Therefore, it seemed promising to evaluate the radioprotective effect of the radical scavenger amifostine in patients receiving high-dose radioiodine therapy. PATIENTS AND METHOD: Quantitative salivary gland scintigraphy using 100 to 120 MBq Tc-99m-pertechnetate was performed in 17 patients with differentiated thyroid cancer prior to and 3 months after radioiodine treatment with 6 GBq I-131. Eight patients were treated with 500 mg/m2 amifostine prior to high-dose radioiodine treatment and compared retrospectively with 9 control patients. Xerostomia was graded according to WHO criteria. RESULTS: In 9 control patients high-dose radioiodine treatment significantly (p < 0.01) reduced Tc-99m-pertechnetate uptake by 35.4 +/- 22.0% and 31.7 +/- 21.1% in parotid and submandibular glands, respectively. Of these 9 patients, 3 exhibited xerostomia Grade I (WHO). In contrast, in 8 amifostine-treated patients, there was no significant (p = 0.878) decrease in parenchymal function following high-dose radioiodine treatment, and xerostomia did not occur in any of them. CONCLUSION: Parenchymal damage in salivary glands induced by high-dose radioiodine treatment can be reduced significantly by amifostine. This may help to increase patients' quality of life in differentiated thyroid cancer.

Risk and outcome in metastatic malignant melanoma patients receiving DTIC, cisplatin, BCNU and tamoxifen followed by immunotherapy with interleukin 2 and interferon alpha2a.

Combined chemo-/immunotherapy has shown high objective response rates and a significant though small proportion of long-term complete responders in metastatic malignant melanoma. The purpose of this study was to determine response rates, freedom from treatment failure (FFTF) and overall survival in patients with advanced metastatic malignant melanoma treated with combined chemo-/immunotherapy, and to determine the value of a prognostic model for prediction of treatment outcome, FFTF and survival. Sixty-nine patients with metastatic malignant melanoma received combined chemo-/immunotherapy consisting of up to four cycles of DTIC (220 mg m(-2) i.v. days 1-3), cisplatin (35 mg m(-2) i.v. days 1-3), BCNU (150 mg m(-2) i.v. day 1, cycles 1 and 3 only) and tamoxifen (20 mg orally, daily). Two cycles of chemotherapy were followed by 6 weeks of outpatient immunotherapy with combined interleukin 2 (20 x 10(6) IU m(-2) days 3-5, weeks 1 and 4; 5 x 10(6) IU m(-2) days 1, 3, 5, weeks 2, 3, 5, 6) and interferon-alpha (6 x 10(6) IU m(-2) s.c. day 1, weeks 1 and 4; days 1, 3, 5, weeks 2, 3, 5, 6). All patients were evaluated on an intention-to-treat basis. Of 69 patients entered in the study, seven achieved complete remissions and 20 reached partial remissions with an objective response rate of 39% (95% confidence interval 28-52%). Median survival was 11 months, median FFTF was 5 months. Seven patients achieved ongoing long-term remissions, with maximum survival of 58 + months, and maximum FFTF of 58 + months. By Kaplan-Meier survival analysis and two-proportional Cox regression analysis, pretreatment performance status and serum lactic dehydrogenase were statistically significant and independent predictors of survival; risk groups could be defined as (a) the absence of both or (b) the presence of either one or both of these risk factors. Whereas survival and response were significantly influenced by patient risk, no influence could be demonstrated for FFTF. This combined outpatient chemo-/immunotherapy is feasible and results in objective response rates and survival similar to earlier trials. Pretreatment risk, as defined by serum lactate dehydrogenase (LDH) and performance status, has a significant impact on treatment outcome and patient survival.

Pharmacokinetics of recombinant human interleukin-2 in advanced renal cell carcinoma patients following subcutaneous application.

AIMS: The aim of the study was to investigate the pharmacokinetics of recombinant human interleukin-2 (rhIL-2) in patients with metastatic renal cell carcinoma following different subcutaneous (s.c.) administration regimens. METHODS: RhIL-2 was administered subcutaneously to 10 patients according to two different dosing regimens: group A received 20 x 10(6) IU m(-2) once daily and group B 10 x 10(6) IU m(-2) twice daily (every 12 h). Additionally, in all patients the influence of soluble interleukin-2 receptor (sIL-2R) on the pharmacokinetics of rhIL-2 was investigated. RESULTS: The mean area under the serum concentration-time curve to 24 h (AUC(0,24 h)) was 627 IU ml(-1) h in treatment group A and 1130 IU ml(-1) h (P=0.029) in treatment group B. In both study groups Cmax and AUC(0,12 h) were not significantly different. Seventy-two hours after the beginning of s.c. rhIL-2 therapy the sIL-2R increased significantly (P=0.016), and sIL-2R levels over 1200 pmol l(-1) seemed to reduce the AUC. CONCLUSIONS: In patients with metastatic renal cell cancer administration of 20 x 10(6) IU m(-2) of rhIL-2 s.c. in two daily doses (10 x 10(6) IU m(-2) every 12 h) provides better bioavailability and is preferable to the single dose administration.