Validation of the Complexity INdex in SARComas prognostic signature on formalin-fixed, paraffin-embedded, soft-tissue sarcomas.

Background: Prediction of metastatic outcome in sarcomas is challenging for clinical management since they are aggressive and carry a high metastatic risk. A 67-gene expression signature, the Complexity INdex in SARComas (CINSARC), has been identified as a better prognostic factor than the reference pathological grade. Since it cannot be applied easily in standard laboratory practice, we assessed its prognostic value using nanoString on formalin-fixed, paraffin-embedded (FFPE) blocks to evaluate its potential in clinical routine practice and guided therapeutic management. Methods: A code set consisting of 67 probes derived from the 67 genes of the CINSARC signature was built and named NanoCind®. To compare the performance of RNA-seq and nanoString (NanoCind®), we used expressions of various sarcomas (n = 124, frozen samples) using both techniques and compared predictive values based on CINSARC risk groups and clinical annotations. We also used nanoString on FFPE blocks (n = 67) and matching frozen and FFPE samples (n = 45) to compare their level of agreement. Metastasis-free survival and agreement values in classification groups were evaluated. Results: CINSARC strongly predicted metastatic outcome using nanoString on frozen samples (HR = 2.9, 95% CI: 1.23-6.82) with similar risk-group classifications (86%). While more than 50% of FFPE blocks were not analyzable by RNA-seq owing to poor RNA quality, all samples were analyzable with nanoString. When similar (risk-group) classifications were measured with frozen tumors (RNA-seq) compared with FFPE blocks (84% agreement), the CINSARC signature was still a predictive factor of metastatic outcome with nanoString on FFPE samples (HR = 4.43, 95% CI: 1.25-15.72). Conclusion: CINSARC is a material-independent prognostic signature for metastatic outcome in sarcomas and outperforms histological grade. Unlike RNA-seq, nanoString is not influenced by the poor quality of RNA extracted from FFPE blocks. The CINSARC signature can potentially be used in combination with nanoString (NanoCind®) in routine clinical practice on FFPE blocks to predict metastatic outcome.

Breast implant-associated anaplastic large cell lymphoma: two distinct clinicopathological variants with different outcomes.

BACKGROUND: ALK-negative anaplastic large cell lymphoma associated with breast implant (i-ALCL) has been recently recognized as a distinct entity. Among 43 830 lymphomas registered in the French Lymphopath network since 2010, 300 breast lymphomas comprising 25 peripheral T-cell lymphomas (PTCL) were reviewed. Among PTCL, ALK-negative ALCL was the most frequent and all of them were associated with breast implants. PATIENTS AND METHODS: Since 2010, all i-ALCL cases were collected from different institutions through Lymphopath. Immuno-morphologic features, molecular data and clinical outcome of 19 i-ALCLs have been retrospectively analyzed. RESULTS: The median age of the patients was 61 years and the median length between breast implant and i-ALCL was 9 years. Most implants were silicone-filled and textured. Implant removal was performed in 17 out of 19 patients with additional treatment based on mostly CHOP or CHOP-like chemotherapy regimens (n = 10/19) or irradiation (n = 1/19). CHOP alone or ABVD following radiation without implant removal have been given in two patients. The two clinical presentations, i.e. effusion and less frequently tumor mass correlated with distinct histopathologic features: in situ i-ALCL (anaplastic cell proliferation confined to the fibrous capsule) and infiltrative i-ALCL (pleomorphic cells massively infiltrating adjacent tissue with eosinophils and sometimes Reed-Sternberg-like cells mimicking Hodgkin lymphoma). Malignant cells were CD30-positive, showed a variable staining for EMA and were ALK negative. Most cases had a cytotoxic T-cell immunophenotype with variable T-cell antigen loss and pSTAT3 nuclear expression. T-cell receptor genes were clonally rearranged in 13 out of 13 tested cases. After 18 months of median follow-up, the 2-year overall survival for in situ and infiltrative i-ALCL was 100% and 52.5%, respectively. CONCLUSIONS: In situ i-ALCLs have an indolent clinical course and generally remain free of disease after implant removal. However, infiltrative i-ALCLs could have a more aggressive clinical course that might require additional therapy to implant removal.

[Radiotherapy as conservative therapy for sarcomas within the irradiated field]. / Place de la radiothérapie dans le traitement conservateur des sarcomes en territoire irradié

PURPOSE: To describe long-term outcome after combined-modality treatment including radiation therapy in patients with localized sarcoma within irradiated field. PATIENTS AND METHODS: Individual clinical data from all consecutive patients diagnosed and treated for a localized sarcoma within irradiated field between January 2000 and October 2011 at the Institut Claudius-Regaud, Toulouse, France, were retrospectively reviewed. RESULTS: Twenty-seven patients were eligible for this study. Ten patients were re-irradiated with a rate of unresectable, gross or microscopically positive margins disease significantly higher than the rest of the cohort (90% vs. 12%; P<0.001). After a median follow-up of 3.8 years, there is a non-significant trend toward longer 4-year relapse free survival in the subgroup of patients who received adjuvant or definitive radiation therapy compared to the rest of the cohort (53% vs. 27%; P=0.09) with an acceptable toxicity profile allowing conservative management. CONCLUSION: The complete surgical resection sarcoma within irradiated field is often difficult to achieve enhancing the risk of relapse. Radiation therapy should be discussed when faced with an unresectable tumour or after suboptimal surgery as part of intensified local management with a curative intent.

Role of radiation therapy in the conservative management of sarcoma within an irradiated field.

PURPOSE: To report on clinical outcome and toxicity profile after combined treatment that included radiation therapy (RT) in patients with localized sarcoma within an irradiated field. PATIENTS AND METHODS: Individual clinical data from all consecutive patients diagnosed and treated for a localized SIF between January 2000 and October 2011 at the Institut Claudius Regaud, Toulouse, France, were retrospectively reviewed. Outcomes of patients with SIF who underwent adjuvant or definitive radiotherapy were compared with patients who did not receive further RT. RESULTS: Of the 27 patients eligible for this study: surgery alone (S), surgery followed by RT (S + RT) or definitive RT (RT) was performed in 16, 8 and 2 cases respectively. The rate of unresectable, gross or microscopically positive margin disease among the 10 re-irradiated patients was significantly higher than the non re-irradiated group (90% vs. 12% p < 0.001). After a median follow-up of 3.8 years, there was a trend toward longer survival and better local control in the subgroup of patients who received adjuvant or definitive RT compared to the rest of the cohort with an acceptable toxicity profile. The 4-year relapse free survival rates of patients treated with and without RT were 53% and 27% respectively (p = 0.09). CONCLUSION: SIF complete surgical resection is often difficult to achieve, enhancing the risk of relapse. RT should be discussed in case of unresectable tumor or after suboptimal surgery as part of intensified local management that has a curative intent.

Dual role of sphingosine kinase-1 in promoting the differentiation of dermal fibroblasts and the dissemination of melanoma cells.

Despite progress in the understanding of the biology and genetics of melanoma, no effective treatment against this cancer is available. The adjacent microenvironment has an important role in melanoma progression. Defining the molecular signals that control the bidirectional dialog between malignant cells and the surrounding stroma is crucial for efficient targeted therapy. Our study aimed at defining the role of sphingosine-1-phosphate (S1P) in melanoma-stroma interactions. Transcriptomic analysis of human melanoma cell lines showed increased expression of sphingosine kinase-1 (SPHK1), the enzyme that produces S1P, as compared with normal melanocytes. Such an increase was also observed by immunohistochemistry in melanoma specimens as compared with nevi, and occurred downstream of ERK activation because of BRAF or NRAS mutations. Importantly, migration of melanoma cells was not affected by changes in SPHK1 activity in tumor cells, but was stimulated by comparable modifications of S1P-metabolizing enzymes in cocultured dermal fibroblasts. Reciprocally, incubation of fibroblasts with the conditioned medium from SPHK1-expressing melanoma cells resulted in their differentiation to myofibroblasts, increased production of matrix metalloproteinases and enhanced SPHK1 expression and activity. In vivo tumorigenesis experiments showed that the lack of S1P in the microenvironment prevented the development of orthotopically injected melanoma cells. Finally, local tumor growth and dissemination were enhanced more efficiently by coinjection of wild-type skin fibroblasts than by fibroblasts from Sphk1(-/-) mice. This report is the first to document that SPHK1/S1P modulates the communication between melanoma cells and dermal fibroblasts. Altogether, our findings highlight SPHK1 as a potential therapeutic target in melanoma progression.

Trastuzumab induced in vivo tissue remodelling associated in vitro with inhibition of the active forms of AKT and PTEN and RhoB induction in an ovarian carcinoma model.

BACKGROUND: The incidence of ovarian cancer has been increasing worldwide and it is currently the leading cause of death from gynaecological malignancy. Unlike breast cancer, the prognostic role of the human epidermal growth factor receptor-2 (HER-2) in ovarian carcinoma remains controversial. METHODS: The aim of this preclinical study was to further characterise the biological, molecular and cellular effects of trastuzumab (Herceptin) using NIH-OVCAR-3 and derived cell lines both in vitro and in vivo. RESULTS: In vitro assessments have shown that trastuzumab treatment inhibited total and phosphorylated HER-2. This was associated with inhibition of the phosphorylated form of phosphatase and tensin homologue (PTEN), mitogen-activated protein kinase and AKT, and the total level of p27(kip). Inhibition of PTEN is associated with phosphorylated MEK1/2 upregulation, suggesting a specific inhibition of the protein phosphatase function of PTEN. Moreover, trastuzumab induced the upregulation of RhoB. These molecular modifications promote inhibition of cell migration and potentially restoration of tumour cell contact inhibition. RhoB induction in NIH-OVCAR-3 control cell lines mimics the molecular and cellular trastuzumab long-time exposition effects. RhoB inhibition in NIH-OVCAR-3 long-time exposed to trastuzumab cell line reverses the cellular and molecular effects observed in this model. In vivo examinations have shown that these changes are also associated with the restoration of structural, morphological and normal functions of the peritoneum of an ovarian carcinoma mouse model. CONCLUSION: These results provide an indication of the mechanisms underlying the anti-tumour activity of trastuzumab that strongly implicate RhoB in an ovarian carcinoma model that does not show HER-2 amplification or overexpression. These findings highlight that trastuzumab effects involve a possible cross-talk between RhoB and PTEN in the early stages of tumour re-growth in a model of micrometastatic ovarian cancer.

Histological regression in primary melanoma: not a predictor of sentinel lymph node metastasis in a cohort of 397 patients.

BACKGROUND: Regression has been proposed as a potential marker of dissemination in thin melanomas. Previous studies have shown conflicting results. OBJECTIVE: To determine if regression in melanoma is associated with an increased risk of sentinel lymph node (SLN) metastasis. METHODS: A cohort analysis was conducted. Data on all patients were collected on a standardized case report form during 10 years. A total of 397 consecutive patients with melanoma who underwent a SLN biopsy were analysed. All cases of melanoma and SLN biopsies were examined by the same two pathologists. Differences between melanomas with and without SLN metastasis were compared using Fisher's exact test or the two-sample t-test and the chi(2) test. Multivariable logistic regression was used to adjust for possible confounding factors. RESULTS: We analysed 397 patients (411 melanomas) who underwent a SLN biopsy. The median Breslow index was 1.8 mm (interquartile range 1.1-3). Regression was observed in 23% (n = 94). SLN metastases were observed in 26% (n = 106). The frequency of SLN metastasis was 16% in melanomas with regression and 29% without regression (P = 0.012). The adjusted odds ratio (OR) for regressive melanoma was 0.9 [95% confidence interval (CI) 0.4-1.9; P = 0.777]. The risk of SLN metastasis was increased in melanoma cases with a Breslow index from 1.5 to < 2.0 mm (adjusted OR 3.1; 95% CI 1.4-7.1; P = 0.006) and >or= 2.0 mm (adjusted OR 3.5; 95% CI 1.7-7.4; P = 0.001) and ulceration of the melanoma (adjusted OR 1.8; 95% CI 1.1-3.2; P = 0.03). CONCLUSION: Regression is not an independent predictor of the risk of SLN metastasis in melanoma.

Cetuximab potentiates oxaliplatin cytotoxic effect through a defect in NER and DNA replication initiation.

Preclinical studies have demonstrated that the chemotherapeutic action of oxaliplatin, a third generation platinum derivative, is improved when combined with cetuximab, a monoclonal antibody inhibitor of epidermal growth factor receptors. To explore the mechanism of this synergistic benefit, we used HCT-8 and HCT-116, two human colon cancer cell lines, respectively, responsive and non-responsive to the oxaliplatin/cetuximab combination. We examined the effect of drug exposure on glutathione-S-transferase-mediated oxaliplatin detoxification, DNA-platinum adducts formation, cell cycle distribution, apoptosis, and the expression of multiple targets involved in DNA replication, recombination, and repair. The major changes we found in HCT-8 were a stimulation of oxaliplatin-DNA adduct formation associated with reduced expression of the key enzyme (excision repair cross complementation group1: ERCC1) in the key repair process of oxaliplatin-DNA platinum adduct, the nucleotide excision repair (NER), both at the mRNA and protein levels. We also observed a reduced expression of factors involved in DNA replication initiation, which correlates with an enrichment of cells in the G1 phase of the cell cycle as well as an acceleration of apoptosis. None of these changes occurred in the non-responsive HCT-116 cell that we used as a negative control. These findings support the fact that cetuximab potentiates the oxaliplatin-mediated cytotoxic effect as the result of inhibition of NER and also DNA replication initiation.

Novel synergistic mechanism for sst2 somatostatin and TNFalpha receptors to induce apoptosis: crosstalk between NF-kappaB and JNK pathways.

Somatostatin is a multifunctional hormone that modulates cell proliferation, differentiation and apoptosis. Mechanisms for somatostatin-induced apoptosis are at present mostly unsolved. Therefore, we investigated whether somatostatin receptor subtype 2 (sst2) induces apoptosis in the nontransformed murine fibroblastic NIH3T3 cells. Somatostatin receptor subtype 2 expression induced an executioner caspase-mediated apoptosis through a tyrosine phosphatase SHP-1 (Src homology domain phosphatase-1)-dependent stimulation of nuclear factor kappa B (NF-kappaB) activity and subsequent inhibition of the mitogen-activated protein kinase JNK. Tumor necrosis factor alpha (TNFalpha) stimulated both NF-kappaB and c-Jun NH2-terminal kinase (JNK) activities, which had opposite action on cell survival. Importantly, sst2 sensitized NIH3T3 cells to TNFalpha-induced apoptosis by (1) upregulating TNFalpha receptor protein expression, and sensitizing to TNFalpha-induced caspase-8 activation; (2) enhancing TNFalpha-mediated activation of NF-kappaB, resulting in JNK inhibition and subsequent executioner caspase activation and cell death. We have here unraveled a novel signaling mechanism for a G protein-coupled receptor, which directly triggers apoptosis and crosstalks with a death receptor to enhance death ligand-induced apoptosis.

Selective inhibition of HER2 inhibits AKT signal transduction and prolongs disease-free survival in a micrometastasis model of ovarian carcinoma.

Although first-line chemotherapy induces complete clinical remission in many cases of epithelial ovarian cancer, relapse usually occurs 18-28 months from diagnosis owing to micrometastases. The present study aimed to evaluate the effect of trastuzumab on disease-free and overall survival in a specially designed murine model of ovarian cancer (OVCAR-3), which mimicked the natural history of human micrometastatic disease. Trastuzumab can cure the mice if started soon after induction chemotherapy. It can modestly inhibit the proliferation through mitogen-activated protein kinase signal transduction and clearly inhibit AKT phosphorylation, which is involved in survival pathway. As OVCAR-3 cell lines show no HER2 amplification or overexpression, these results warrant further studies to assess the efficacy of trastuzumab in the early stage of relapse in cancer models other than those overexpressing HER2.

Intraoperative testosterone assay for virilizing ovarian tumor topographic assessment: report of a Leydig cell tumor of the ovary in a premenopausal woman with an adrenal incidentaloma.

Ovarian virilizing tumors are rare and can lead to assessment difficulties because of their small size. A 41-yr-old female was referred for evaluation of hirsutism that had increased within the previous 3 yr. Menstrual cycle length was normal. Plasma testosterone was 3.9 ng/ml (normal range, 0.2-0.8 ng/ml), was not suppressible by 2 mg dexamethasone (4.3 ng/ml), and was increased (6.3 ng/ml) after three daily injections of hCG (5000 IU). Abdominal computed tomography scan showed an adrenal nodule (13 x 6 mm) that remained unchanged after 3 months. Ultrasound examination of the pelvis was normal. Ovarian and adrenal venous catheterization did not yield additional information. Topographic assessment was made by intraoperative measurement of testosterone in the samples taken from each ovarian vein (competitive chemiluminescent immunoassay ADVIA Centaur; right ovarian vein, 105 ng/ml; left ovarian vein, 5 ng/ml; peripheral blood, 7 ng/ml). Right annexectomy resulted in normalization of testosterone levels (0.22 ng/ml). Histopathological examination found a Leydig cell tumor of hilar type (1.5 cm). This observation illustrates the usefulness of intraoperative measurement of testosterone by a rapid automated technique for topographic assessment of ovarian virilizing tumor in premenopausal women.

The AF-1 activation-function of ERalpha may be dispensable to mediate the effect of estradiol on endothelial NO production in mice.

Two isoforms of estrogen receptor (ER) have been described: ERalpha and ERbeta. The initial gene targeting of ERalpha, consisting in the introduction of a Neo cassette in exon 1 [alphaERKO, hereafter called ERalpha-Neo KO (knockout)], was reported in 1993. More recently, another mouse deficient in ERalpha because of the deletion of exon 2 (ERalphaKO, hereafter called ERalpha-delta2 KO) was generated. In ovariectomized ERalpha-wild-type mice, estradiol (E(2)) increases uterine weight and basal production of endothelial nitric oxide (NO). Both of these effects are abolished in ERalpha-delta2 KO mice. In contrast, we show here that both of these effects of E(2) are partially (uterine weight) or totally (endothelial NO production) preserved in ERalpha-Neo KO. We also confirm the presence of two ERalpha mRNA splice variants in uterus and aorta from ERalpha-Neo KO mice. One of them encodes a chimeric ERalpha protein (ERalpha55), partially deleted in the A/B domain, that was detected in both uterus and aorta by Western blot analysis. The other ERalpha mRNA splice variant codes for an isoform deleted for the A/B domain (ERalpha46), which was detected in uterus of ERalpha-Neo KO, and wild-type mice. This protein isoform was not detected in aorta. The identification of these two N-terminal modified isoforms in uterus, and at least one of them in aorta, probably explains the persistence of the E(2) effects in ERalpha-Neo KO mice. Furthermore, ERalpha-Neo KO mice may help in the elucidation of the specific functions of full-length ERalpha (ERalpha66) and ERalpha46, both shown to be physiologically generated in vivo.

Signal transduction of somatostatin receptors negatively controlling cell proliferation.

Somatostatin acts as an inhibitory peptide of various secretory and proliferative responses. Its effects are mediated by a family of G-protein-coupled receptors (sst1-5) that can couple to diverse signal transduction pathways such as inhibition of adenylate cyclase and guanylate cyclase, modulation of ionic conductance channels, and protein dephosphorylation. The five receptors bind the natural peptide with high affinity but only sst2, sst5 and sst3 bind the short synthetic analogues. Somatostatin negatively regulates the growth of various normal and tumour cells. This effect is mediated indirectly through inhibition of secretion of growth-promoting factors, angiogenesis and modulation of the immune system. Somatostatin can also act directly through sst receptors present on target cells. The five receptors are expressed in various normal and tumour cells, the expression of each receptor being receptor subtype and cell type specific. According to the receptor subtypes, distinct signal transduction pathways are involved in the antiproliferative action of somatostatin. Sst1, 4 and 5 modulate the MAP kinase pathway and induce G1 cell cycle arrest. Sst3 and sst2 promote apoptosis by p53-dependent and -independent mechanisms, respectively.

Inhibition of growth and metastatic progression of pancreatic carcinoma in hamster after somatostatin receptor subtype 2 (sst2) gene expression and administration of cytotoxic somatostatin analog AN-238.

The sst2 somatostatin receptor mediates the antiproliferative effects of somatostatin analogs. The present study demonstrates that stable expression of sst2 in the hamster pancreatic cancer cells PC-1 and PC-1.0 activates an autocrine negative loop leading to an in vitro inhibition of cell proliferation. In vivo studies conducted in Syrian golden hamsters after orthotopic implantation of PC-1.0 cells showed that both tumor growth and metastatic progression of allografts containing 100% of sst2-expressing cells were significantly inhibited for up to 20 days after implantation, as compared with control allografts that did not express sst2. A local antitumor bystander effect was observed after induction of mixed tumors containing a 1:3 ratio of sst2-expressing cells to control cells. Tumor volume and incidence of metastases of mixed tumors were significantly reduced at day 13 post implantation. This effect decreased with time as at day 20, growth of mixed tumors was similar to that of control tumors. After administration of the cytotoxic somatostatin conjugate AN-238 on day 13, antitumor bystander effect observed in mixed tumors was significantly extended to day 20. We also observed that in vitro invasiveness of sst2-expressing PC-1.0 cells was significantly reduced. Tyrosine dephosphorylation of E-cadherin may participate in restoring the E-cadherin function, reducing in turn pancreatic cancer cell motility and invasiveness. This dephosphorylation depends on the tyrosine phosphatase src homology 2-containing tyrosine phosphatase 1 (SHP-1) positively coupled to sst2 receptor. The inhibitory effect of sst2 gene expression on pancreatic cancer growth and invasion combined with chemotherapy with targeted cytotoxic somatostatin analog administration provides a rationale for a therapeutic approach to gene therapy based on in vivo sst2 gene transfer.

The expression of CD70 and CD80 by gene-modified tumor cells induces an antitumor response depending on the MHC status.

The expression of costimulatory molecules such as CD70 or CD80 by gene-modified tumor cells has been shown to enhance the antitumor immune response based mainly on T lymphocytes. However, most human tumors show defects of major histocompatibility complex (MHC) expression, preventing them from being recognized by MHC-restricted T cells. To investigate if coexpression of CD70 and CD80 costimulatory molecules induces comparable antitumor responses in low and high MHC-expressing tumor cells, we used two low immunogenic murine tumor models, the B16.F10 melanoma and the TS/A mammary adenocarcinoma cell lines expressing, respectively, low and high levels of MHC class I molecules. Transfection of both CD70 and CD80 genes resulted in an increased capacity of gene-modified tumor cells to costimulate in vitro the proliferation and cytokine production of optimally activated lymphoid cells. Coexpression of CD70 and CD80 by the two tumor cell lines, TS/A and B16.F10, resulted in both cases in partial regression of subcutaneous tumors. Immunochemical analysis and studies in nude mice showed that, even in the B16.F10 model, T cells had a significant role in the antitumor response induced by combining CD70 and CD80. However, rejection of the CD70/CD80-transfected tumor cells appeared more effective in the MHC class I high TS/A model, leading to a protection against parental tumor cells. B16.F10 and TS/A transfectants were then tested with fibroblasts genetically modified to secrete interleukin-12 (IL-12) as a therapeutic vaccine in mice bearing parental tumors. In the two models tested, the injections of irradiated IL-12 and CD70/CD80 gene-modified cells generated an antitumor response to established tumors leading to the slowing down of the tumor growth rate. Although the mechanisms remain to be defined, these findings suggest that the combination of several immuno-modulatory molecules could provide additional strategies for cancer immuno-gene therapy, even for MHC expression-deficient tumors.

In vivo patterns of Bcl-2 family protein expression in breast carcinomas in relation to apoptosis.

The expression of the pro-apoptotic proteins (Bax, Bak) and anti-apoptotic proteins (Bcl-2, Bcl-X, Mcl-1) was studied by immunohistochemistry in 110 invasive ductal breast carcinomas. The results were correlated with tumour grade, expression of oestrogen receptor (ER) and p53 protein, and the apoptotic index by combined morphology, immunohistochemistry, and a terminal UTP nick end labelling (TUNEL) procedure. Overall, Bcl-2, Bcl-X, Mcl-1, Bax, Bak, ER, and p53 were detected in 62, 75, 68, 75, 60, 68 and 26 per cent of the cases respectively, but at different levels in each case. A high apoptotic index was correlated with high tumour grade (p<0.001), overexpression of p53 (p<0.001), Bak expression (p<0.001), and low expression of Bcl-2 (p<0.001) and ER (p<0.001). No correlation was found between the apoptotic index and Bax, Bcl-X, and Mcl-1 immunostaining results. The expression of Bcl-2 and Bcl-X was correlated to that of ER. Overall, the results of this study strongly suggest that Bcl-2 and Bak expression is critical in regulating apoptosis in breast carcinomas.

Ex vivo discrimination between normal and pathological tissues in human breast surgical biopsies using bioimpedance spectroscopy.

Ex vivo bioimpedance data measured on normal and cancerous female breast tissues are reported. They clearly show that the electrical properties of normal tissues, surrounding tissues, and carcinoma are different. These differences lie in the conductivity, in the characteristic frequency (frequency of the maximum of the imaginary part of the bioimpedance), and also in the shape of the Bode plots. Modeling using an R-S-Zcpe model is reported as well as indexes extracted from the real and imaginary parts of the bioimpedance. Even if a classification of the different types of tissues remains a difficult task and leads to much less precise diagnosis than microscopic examination, the electrical behavior of mammary tissue could be used to develop a noninvasive technique for early breast cancer detection.

[Granular cell tumors of the skin of nonneural origin: report of 8 cases]. / Tumeurs à cellules granuleuses de la peau d'origine non nerveuse: étude de 8 cas.

We report six cases of benign fibrous histiocytoma, one case of dermatomyofibroma, one case of cutaneous leiomyosarcoma with a granular cell component. Besides the clinical, histologic and immunohistochemical features of the primary lesion, these tumors do not express S100 protein in contrast to the classic granular cell tumor described by Abrikossoff. Such a component has no implication in prognosis, which remains related to the main lesion. Ignorance of this rare event can lead to misdiagnosis, requiring a total revision of the granular cell tumor entity.

Gene therapy for pancreatic carcinoma: local and distant antitumor effects after somatostatin receptor sst2 gene transfer.

Human pancreatic adenocarcinomas lose the ability to express sst2, the somatostatin receptor, which mediates the antiproliferative effect of somatostatin. Reintroducing sst2 into human pancreatic cancer cells by stable expression evokes an autocrine negative feedback loop leading to a constitutive activation of the sst2 gene and an inhibition of cell proliferation and tumorigenicity. In vivo studies have been conducted in athymic mice to investigate the antitumor bystander effects resulting from the transfer of the sst2 gene into human pancreatic cancer cell line BxPC-3. In mixing experiments, a local bystander effect was observed: mixed tumors containing a ratio of sst2-expressing cells to control cells of 25:75, 50:50, and 75:25 grew with a time delay of 31, 44, and 50 days, respectively, when compared with control tumors derived from control cells. Tumors containing 100% sst2-expressing cells remained quiescent for up to 80 days. A significant increase in apoptosis and a decrease in the Ki67 index were detected in mixed and sst2 tumor when compared with control tumors. In combined experiments, mice were separately xenografted with control cells on one flank and with sst2-expressing cells on the other flank. A distant antitumor effect was induced: growth of control tumors was delayed by 33 days, the Ki67 index decreased significantly, and apoptosis increased when compared with control tumors that grew alone. The distant bystander effect may be explained in part by a significant increase in serum somatostatin-like immunoreactivity levels resulting from the autocrine feedback loop produced by sst2-expressing cells and inducing an upregulation of the type 1 somatostatin receptor, sst1, which also mediates the antiproliferative effect of somatostatin. In conclusion, the local and distant antitumor bystander effects obtained in this experimental model suggest that sst2 gene transfer may represent a new therapy for pancreatic cancer.