Fully automated radiolabeling of [68Ga]Ga-EMP100 targeting c-MET for PET-CT clinical imaging.

BACKGROUND: c-MET is a transmembrane receptor involved in many biological processes and contributes to cell proliferation and migration during cancer invasion process. Its expression is measured by immunehistochemistry on tissue biopsy in clinic, although this technique has its limitations. PET-CT could allow in vivo mapping of lesions expressing c-MET, providing whole-body detection. A number of radiopharmaceuticals are under development for this purpose but are not yet in routine clinical use. EMP100 is a cyclic oligopeptide bound to a DOTA chelator, with nanomolar affinity for c-MET. The aim of this project was to develop an automated method for radiolabelling the radiopharmaceutical [68Ga]Ga-EMP100. RESULTS: The main results showed an optimal pH range between 3.25 and 3.75 for the complexation reaction and a stabilisation of the temperature at 90 °C, resulting in an almost complete incorporation of gallium-68 after 10 min of heating. In these experiments, 90 µg of EMP-100 peptide were initially used and then lower amounts (30, 50, 75 µg) were explored to determine the minimum required for sufficient synthesis yield. Radiolysis impurities were identified by radio-HPLC and ascorbic acid and ethanol were used to improve the purity of the compound. Three batches of [68Ga]Ga-EMP100 were then prepared according to the optimised parameters and all met the established specifications. Finally, the stability of [68Ga]Ga-EMP100 was assessed at room temperature over 3 h with satisfactory results in terms of appearance, pH, radiochemical purity and sterility. CONCLUSIONS: For the automated synthesis of [68Ga]Ga-EMP100, the parameters of pH, temperature, precursor peptide content and the use of adjuvants for impurity management were efficiently optimised, resulting in the production of three compliant and stable batches according to the principles of good manufacturing practice. [68Ga]Ga-EMP100 was successfully synthesised and is now available for clinical development in PET-CT imaging.

Microvasculature partial endothelial mesenchymal transition in early posttransplant biopsy with acute tubular necrosis identifies poor recovery renal allografts.

Acute tubular necrosis (ATN), a frequent histopathological feature in the early post-renal transplant biopsy, affects long-term graft function. Appropriate markers to identify patients at risk of no or incomplete recovery after delayed graft function are lacking. In this study, we first included 41 renal transplant patients whose biopsy for cause during the first month after transplantation showed ATN lesions. Using partial microvasculature endothelial (fascin, vimentin) and tubular epithelial (vimentin) to mesenchymal transition markers, detected by immunohistochemistry, we found a significant association between partial endothelial to mesenchymal transition and poor graft function recovery (Spearman's rho = -0.55, P = .0005). Transforming growth factor-ß1 was strongly expressed in these phenotypic changed endothelial cells. Extent of ATN was also correlated with short- and long-term graft dysfunction. However, the association of extensive ATN with long-term graft dysfunction (24 months posttransplant) was observed only in patients with partial endothelial to mesenchymal transition marker expression in their grafts (Spearman's rho = -0.64, P = .003), but not in those without. The association of partial endothelial to mesenchymal transition with worse renal graft outcome was confirmed on 34 other early biopsies with ATN from a second transplant center. Our results suggest that endothelial cell activation at the early phase of renal transplantation plays a detrimental role.

Prevalence of Microsatellite Instability in Intraductal Papillary Mucinous Neoplasms of the Pancreas.

Microsatellite instability (MSI) caused by mismatch repair deficiency (dMMR) is detected in a small proportion of pancreatic ductal adenocarcinomas (PDACs). dMMR and MSI have been associated with responses of metastatic tumors, including PDACs, to immune checkpoint inhibitor therapy. We performed immunohistochemical analyses of a 445 PDAC specimens, collected from consecutive patients at multiple centers, to identify those with dMMR, based on loss of mismatch repair proteins MLH1, MSH2, MSH6, and/or PMS2. We detected dMMR in 1.6% of tumor samples; we found dMMR in a larger proportion of intraductal papillary mucinous neoplasms-related tumors (4/58, 6.9%) than non- intraductal papillary mucinous neoplasms PDAC (5/385, 1.3%) (P = .02). PDACs with dMMR contained potentially immunogenic mutations because of MSI in coding repeat sequences. PDACs with dMMR or MSI had a higher density of CD8+ T cells at the invasive front than PDACs without dMMR or MSI (P = .08; Fisher exact test). A higher proportion of PDACs with dMMR or MSI expressed the CD274 molecule (PD-L1, 8/9) than PDACs without dMMR or MSI (4/10) (P = .05). Times of disease-free survival and overall survival did not differ significantly between patients with PDACs with dMMR or MSI vs without dMMR or MSI. Studies are needed to determine whether these features of PDACs with dMMR or MSI might serve as prognostic factors.

Nonsmall cell lung cancer from HIV-infected patients expressed programmed cell death-ligand 1 with marked inflammatory infiltrates.

OBJECTIVE: Immunotherapies targeting the programmed cell death-1 (PD-1)/PD-ligand 1 (PD-L1) checkpoint improved prognosis in lung cancer. PD-1/PD-L1 status, however, has not been investigated in human immunodeficiency virus (HIV)-positive patients. This study assessed PD-L1 status and tumor immune-cell infiltration in nonsmall cell lung cancer (NSCLC) in HIV patients. METHODS: Consecutive HIV patients treated between 1996 and 2014 were enrolled. PD-L1 tumor expression was assessed using immunohistochemistry with two antibodies (clones 5H1 and E1L3N), and tumor immune-cell infiltration with CD3, CD4, CD8, CD20, CD163, and MPO. PD-L1 expression and immune infiltration results were compared with those of 54 NSCLCs from unknown HIV status patients. RESULTS: Thirty-four HIV-positive patients were evaluated: predominantly men (88.2%) (median age: 51.1 years) presenting stage IV (38.2%) adenocarcinomas (76.5%). The median blood CD4 count was 480 cells/µL (86-1120) and 64% exhibited undetectable viral load. The PD-L1 score (percentage of positive cells × intensity) was higher in HIV-positive than HIV-undetermined patients with the E1L3N clone [median (range) 0 (0-150) versus 0 (0-26.7), P = 0.047], yet not with the 5H1 clone [0 (0-120) versus 0 (0-26.7) P = 0.07, respectively]. PD-L1 expression frequency did not differ between both cohorts (18.7 versus 9.3% using E1L3N and 10 versus 5.6% using 5H1 clone, respectively). There were significantly greater cytotoxic T-cell (P < 0.001), B-lymphocyte (P = 0.005), and activated macrophage (P < 0.001) infiltrations in the HIV-positive patients, but no differences for CD4 T cells. CONCLUSION: Tumors in HIV-positive patients seem to express higher PD-L1 levels with increased immune infiltration, supporting their inclusion in clinical trials assessing immune checkpoint inhibitors.

Lepidic predominant adenocarcinoma and invasive mucinous adenocarcinoma of the lung exhibit specific mucin expression in relation with oncogenic drivers.

OBJECTIVES: To evaluate MUC1, MUC2, MUC5B, MUC5AC, and MUC6 expression in invasive lepidic predominant adenocarcinoma (LPA) and invasive mucinous adenocarcinoma (IMA) of the lung, and the impact of oncogenic drivers. MATERIALS AND METHODS: MUC1, MUC2, MUC5B, MUC5AC, MUC6, TTF1 and Hnf4α immunohistochemistry was performed on surgical samples from 52 patients with IMA (n=25) or LPA (n=27). We searched for EGFR, KRAS, BRAF, and HER2 mutations and ALK, ROS1, and NRG1 rearrangements. RESULTS: MUC1, MUC2, MUC5B, MUC5AC, and MUC6 expression was detected in tumor cells in 77%, 2%, 63%, 36%, and 21% of cases, respectively. MUC1 was significantly more overexpressed in LPA. MUC5B, MUC5AC, and MUC6 were typically detected in goblet cells and overexpressed in IMA. Hnf4α-positive IMA (n=11) were TTF1-negative and typically did not expressed MUC1 and expressed MUC5AC and MUC6. Hnf4α-negative IMA (n=14) showed a reverse profile of mucins expression, with MUC1 expression and a lack of MUC5AC and MUC6 expression. EGFR-positive status was significantly associated with LPA, MUC1 expression, and no MUC5B, MUC5AC, or MUC6 expression. KRAS-positive status was significantly associated with IMA and MUC5B and MUC5AC expression. CONCLUSIONS: LPA and IMA exhibit specific mucin expression profiles, with MUC1 being associated with LPA, while MUC5B, MUC5AC, and MUC6 were associated with IMA. Hnf4α expression and EGFR and KRAS mutations may play a role in mucin expression profiles of these lung adenocarcinoma subtypes.

Loss of tubular creatinine secretion as the only sign of tubular proximal cell dysfunction in light chain proximal tubulopathy: A case report.

Light chain proximal tubulopathy (LCPT) is a rare disease, characterized by cytoplasmic inclusions of light chain (usually kappa) immunoglobulins. Clinical presentation is usually a Fanconi syndrome. The proximal tubular dysfunction can be incomplete, and exceptional cases of LCPT without any tubular dysfunction have even been described. Here, we report a case of LCPT in which the only sign of proximal tubulopathy is the absence of secretion of creatinine, as assessed by the simultaneous measurement of renal clearance of creatinine and CrEDTA. The loss of tubular creatinine secretion as a sign of tubular proximal cell dysfunction ought to be identified in patients with light chain proximal tubulopathy as it leads to a clinically relevant underestimation of GFR by the creatinine-derived equations. The prevalence and prognostic significance of this particular proximal tubular damage in LCPT remain to be determined.

Sarcomatoid lung carcinomas show high levels of programmed death ligand-1 (PD-L1) and strong immune-cell infiltration by TCD3 cells and macrophages.

OBJECTIVES: Pulmonary sarcomatoid carcinomas (SC) are rare tumors, associated with worse prognosis and resistant to platinum-based regimens. Therapies targeting the PD-1/PD-L1 pathway are an emerging treatment for lung cancer. By characterizing intra-tumoral immune infiltration and evaluating PD-L1 expression, it could be possible to predict the efficacy of these new treatments. MATERIALS AND METHODS: From 1997 to 2013, data from all patients with SC who underwent lung resection was collected. Tumor-immune infiltration and PD-L1 expression were studied by immunochemistry tests, analyzing CD3 (clone SP7), CD4 (clone 1F6), CD8 (clone C8/144b), CD20 (clone L26), CD163 (clone 10D6), MPO (clone 59A5), and PD-L1 (clone 5H1). Results were compared to those of 54 NSCLC. RESULTS: In total, 75 SC were included. Forty (53%) SC expressed PD-L1 vs 11 NSCLC (20%) (p<0.0001). CD3+ tumor-infiltrating lymphocytes and CD163+ tumor-associated macrophages were more important in SC than in NSCLC (median 23% [17-30] of tumoral surface vs 17% [7-27], p=0.011 and 23% [17-30] vs 20% [13-23], p=0.002, respectively). In SC, the presence of Kirsten Ras (KRAS) mutations, blood vessel invasion, and TTF1+ positivity were associated with PDL1 expression. On multivariate analysis, only CD163+ macrophages and blood-vessel invasion were associated with tumoral PD-L1 expression. High levels of tumor-infiltrating lymphocytes (CD3+ or CD4+ and not CD8+) constituted a factor of good prognosis on survival. Interestingly, PD-L1 expression distinguishes subpopulations within tumor-infiltrating lymphocytes (CD3+ or CD4+) with different prognosis CONCLUSIONS: PD-L1 expression was higher in SC than in NSCLC as well as immune-cell infiltration by TCD3 cells and macrophages. This suggests that targeting the PD-1/PD-L1 pathway could represent a new potential therapy.

Expression of somatostatin type-2 and -4 receptor and correlation with histological type in breast cancer.

BACKGROUND: Somatostatin is produced by hypothalamic cells and also by tumors. We were interested to evaluate the somatostatin type 2 (SSTR2) and type 4 (SSTR4) receptor expression on a large sample cohort of breast cancer cases. MATERIALS AND METHODS: We used two different Tissue Micro Arrays (TMA) to evaluate SSTR2 and SSTR4 distribution. We evaluated the correlation between SSTR2 and SSTR4 expression and 18 tumor cells markers. We also assessed SSTR mRNA expression on an independent breast cancer population and correlated levels of SSTR2 and SSTR4 expression to molecular breast cancer subtypes. RESULTS: 268 tumors were analyzed. The tumor overexpression of estrogen receptor was significantly correlated to the expression of SSTR2 (p=0.05) and SSTR4 (p=0.04). On principal component analysis, SSTR2 subtype characterized the luminal tumor type. On an independent breast cancer population, expression of SSTR2 and SSTR4 are independent from Human Epidermal Growth Factor Receptor 2 (Her2) and correlated with luminal tumors. CONCLUSION: Expression of somatostatin receptors is a marker of luminal breast tumors.

High incidence of triple-negative tumors in sub-saharan Africa: a prospective study of breast cancer characteristics and risk factors in Malian women seen in a Bamako university hospital.

OBJECTIVE: Few studies have been conducted on breast cancer in Sub-Saharan Africa and their results have been suspected to be impaired by artefacts. This prospective study was designed to determine tumor and patient characteristics in Mali with control of each methodological step. These data are necessary to define breast cancer treatment guidelines in this country. METHODS: Clinical and tumor characteristics and known risk factors were obtained in a consecutive series of 114 patients. Each technical step for the determination of tumor characteristics [histology, TNM, grade, estrogen (ER) and progesterone receptors (PR), HER2, and Ki67] was controlled. RESULTS: Patients had a mean age of 46 years. Most tumors were invasive ductal carcinomas (94%), T3-T4 (90%) with positive nodes (91%), grade III (78%), and ER (61%) and PR (72%) negative. HER2 was overexpressed in 18% of cases. The triple-negative subgroup represented 46%, displaying a particularly aggressive pattern (90% grade III; 88% Ki67 >20%). CONCLUSION: This study demonstrates the high incidence of aggressive triple-negative tumors in Mali. Apart from a higher prevalence of premenopausal women, no significant difference in risk factors was observed between triple-negative tumors and other tumors. The hormonal therapy systematically prescribed therefore needs to be revised in light of this study.

Eutopic endometrium and peritoneal, ovarian and colorectal endometriotic tissues express a different profile of nectin-1, -3, -4 and nectin-like molecule 2.

STUDY QUESTION: How is the expression of nectins and nectin-like molecules (Necls) detected by immunostaining altered by endometriosis? SUMMARY ANSWER: Our results suggest that Nectin-1, -3, -4 and Necl-2 may contribute to the pathogenesis of endometriosis. Immunostaining of nectins and Necls varies according to the anatomical location of endometriosis. WHAT IS KNOWN AND WHAT THIS PAPER ADDS: Nectin and Necl molecules are immunoglobulin-like cell adhesion molecules involved in apoptosis, cell proliferation and in metastases. Previous studies have demonstrated the involvement of adhesion molecules in the development of endometriotic lesions but no data exist on immunostaining of nectins and Necls molecules in endometriosis. DESIGN, PARTICIPANTS AND SETTING: This retrospective study was conducted in a tertiary-care hospital (Tenon Hospital, Paris, France). Samples were collected from 55 women undergoing endometrial biopsy or surgery for endometriosis and 20 controls having hysterectomy or endometrial biopsy for other reasons; multiple samples were collected from 15 women. We studied the immunostaining of Nectin-1, -3, -4 and Necl-2 in secretory and proliferative endometrium from women with (n = 20) or without endometriosis (i.e. control group, n = 20), and in peritoneal (n = 20), ovarian (n = 20) and colorectal endometriosis (n = 20). MAIN RESULTS: Semi-quantitative immunostaining demonstrated that (1) Necl-2 staining was stronger in all types of endometriotic lesions than in the eutopic endometrium from patients with endometriosis (P < 0.0125) and in ovarian endometriotic cysts compared with other locations (P < 0.001); (2) Nectin-3 staining was stronger in the eutopic endometrium of patients with endometriosis compared with controls (P = 0.03) and in all endometriotic lesions compared with the eutopic endometrium from patients with endometriosis (P < 0.0125); (3) Nectin-4, staining was stronger in the eutopic endometrium of patients with endometriosis compared with controls (P = 0.04) and (4) Nectin-1 staining was significantly increased in colorectal endometriosis compared with other locations (P = 0.004). BIAS, CONFOUNDING AND OTHER REASONS FOR CAUTION: We did not assess the pattern of expression in endometriosis of all nectins and Necl molecules. Indeed, Necl-5 is implicated in many pathophysiological processes such as cell movement and proliferation with potential relevance to endometriosis. GENERALISABILITY TO OTHER POPULATIONS: At present, few data on implication of nectins and Necl molecules in endometriosis exist. Hence, our results should be confirmed by further quantitative studies at protein or RNA levels. STUDY FUNDING/COMPETING INTEREST(S): No funding source. All the authors declare no conflict of interest.

Williams-Beuren syndrome hypercalcemia: is TRPC3 a novel mediator in calcium homeostasis?

Williams-Beuren syndrome (WBS) is a neurodevelopmental disorder associated with hypercalcemia of unknown origin. This syndrome results from the deletion of contiguous genes on chromosome 7, including the general transcription factor IIi gene. The general transcription factor IIi gene encodes TFII-I, which suppresses cell-surface accumulation of transient receptor potential C3 (TRPC3) channels, involved in calcium transport in lymphocytes. We describe the case of a patient with WBS with hypercalcemia associated with abnormal TRPC3 expression. Analysis of peripheral lymphocytes revealed a sharp increase in TRPC3 expression, compared with control patients. To investigate the potential role of TRPC3 in calcium homeostasis, we performed specific immunostaining on the intestine and the kidney, major calcium-regulating tissues. We provide the first demonstration that TRPC3 is expressed in normal digestive epithelium and renal tubules in control patients, and overexpressed in the intestine in the patient with WBS. Taken together, these data suggest that calcium metabolism abnormalities observed in WBS may be attributable to TFII-I haploinsufficiency and subsequent TRPC3 overexpression, thereby increasing both digestive and renal calcium absorption. This original observation prompts further investigation of TRPC3 as a novel actor of calcium homeostasis.

[Somatostatin in breast cancer]. / La somatostatine dans le cancer du sein.

In man, somatostatin is a hormone mostly produced by hypothalamus. It plays different parts in hormonal regulation through many specific receptors in human body. It has also two interesting actions such as an anti-secretory activity, mostly on the gastrointestinal system and an antiproliferative action on tumor cells. Many synthetic somatostatin analogues, more stable than the natural one, have been developed and are already used in digestive surgery to treat postoperative digestive fistula. Also, the development of specific polyclonal antibodies allowed the identification of five specific somatostatin receptors and their localization in different cell species. The presence of the five receptors in breast cancer cells has than been demonstrated. The purpose of this literature review is to clarify the potential antitumor effect of somatastatin analogues in breast cancer; its use as a preventive agent on lymphorrhea after breast surgery and its employment in imaging for early breast cancer detection.

Epidermal growth factor receptor promotes glomerular injury and renal failure in rapidly progressive crescentic glomerulonephritis.

Rapidly progressive glomerulonephritis (RPGN) is a life-threatening clinical syndrome and a morphological manifestation of severe glomerular injury that is marked by a proliferative histological pattern ('crescents') with accumulation of T cells and macrophages and proliferation of intrinsic glomerular cells. We show de novo induction of heparin-binding epidermal growth factor-like growth factor (HB-EGF) in intrinsic glomerular epithelial cells (podocytes) from both mice and humans with RPGN. HB-EGF induction increases phosphorylation of the epidermal growth factor receptor (EGFR, also known as ErbB1) in mice with RPGN. In HB-EGF-deficient mice, EGFR activation in glomeruli is absent and the course of RPGN is improved. Autocrine HB-EGF induces a phenotypic switch in podocytes in vitro. Conditional deletion of the Egfr gene from podocytes of mice alleviates the severity of RPGN. Likewise, pharmacological blockade of EGFR also improves the course of RPGN, even when started 4 d after the induction of experimental RPGN. This suggests that targeting the HB-EGF-EGFR pathway could also be beneficial in treatment of human RPGN.

Discoidin domain receptor 1 null mice are protected against hypertension-induced renal disease.

A frequent complication of hypertension is the development of chronic renal failure. This pathology usually is initiated by inflammatory events and is characterized by the abnormal accumulation of collagens within the renal tissue. The purpose of this study was to investigate the role of discoidin domain receptor 1 (DDR1), a nonintegrin collagen receptor that displays tyrosine-kinase activity, in the development of renal fibrosis. To this end, hypertension was induced with angiotensin in mice that were genetically deficient of DDR1 and in wild-type controls. After 4 or 6 wk of angiotensin II administration, wild-type mice developed hypertension that was associated with perivascular inflammation, glomerular sclerosis, and proteinuria. Systolic pressure increase was similar in the DDR1-deficient mice, but the histologic lesions of glomerular fibrosis and inflammation were significantly blunted and proteinuria was markedly prevented. Immunostaining for lymphocytes, macrophages, and collagens I and IV was prominent in the renal cortex of wild-type mice but substantially reduced in DDR1 null mice. In separate experiments, renal cortical slices of DDR1 null mice showed a blunted response of chemokines to LPS that was accompanied by a considerable protection against the LPS-induced mortality. These results indicate the importance of DDR1 in mediating inflammation and fibrosis. Use of DDR1 inhibitors could provide a completely novel therapeutic approach against diseases that have these combined pathologies.