Pharmacophore modelling as useful tool in the lead compounds identification and optimization

The goal of computer-aided molecular design methods in modern medicinal chemistry is to reduce the overall cost and time associated to the discovery and development of a new drug by identifying the most promising candidates to focus the experimental efforts on. Very often, many drug discovery projects have reached already a well-advanced stage before detailed structural data on the protein target have become available. A possible consequence is that often, medicinal chemists develop novel compounds for a target using preliminary structure–activity information, together with the theoretical models of interactions. Only responses that are consistent with the working hypothesis contribute to an evolution of the used models. Within this framework, the pharmacophore approach has proven to be successful, allowing the perception and understanding of key interactions between a receptor and a ligand[1]. In recent years, our research group exploited this useful modeling tool with the aim to identify new chemical entities and/or optimizing known lead compounds to obtain more active drugs in the field of antitumor, antiviral, and antibacterial drugs. In this communication, we present an overview of our recent works in which we used the pharmacophore modelling approach combined with induced fit docking, 3D-QSAR approach, and HTVS for the analysis of drug-receptor interactions and the discovery of new inhibitors of IKKβ, Bcl-xl, and c-kit tyrosine kinase, all targets involved into the initiation and the development of different types of cancer[2-5]

Different expression of thymidylate synthase in primary tumour and metastatic nodes in breast cancer patients.

BACKGROUND: To date an accurate evaluation of predictive markers in breast cancer is mainly conducted at the primary site, although the main goal of the adjuvant therapy is the control of micrometastases. Adjuvant therapy drugs need a high proliferative cell rate to be effective. The proliferating activity can be evaluated by the Ki-67 marker and even by thymidylate synthase (TS), a cell cycle enzyme present in proliferating cells. In this study the TS levels in primary tumours were compared to those of their metastases. PATIENTS AND METHODS: The TS expression and Ki-67 were evaluated by means of immunohistochemistry in 80 primary breast tumours (PTs) and in their matched axillary metastatic lymph-nodes (ALNs). RESULTS: In 16% of patients, malignant cells of involved nodes showed a lower TS expression than the PTs. In the same group, we also found a lower number of Ki-67 immunoreactive cells in lymph node metastases when compared with primary tumours. CONCLUSION: The group of patients with lower TS and Ki-67 expression in lymph node metastatic cells may be less sensitive to 5-fluorouracil and high dose methotrexate requiring them to be treated with other drug combinations

Lymph node metastases displaying lower Ki-67 immunostaining activity than the primary breast cancer

The aim of the study was to verify by Ki-67 immunostaining if any difference exists in the cell proliferating fraction between primary breast tumors (PTs) and matching positive axillary lymph nodes (ALNs). PATIENTS AND METHODS: Immunohistochemistry with the monoclonal antibody against Ki-67 was performed in 160 node-positive breast carcinomas and in their respective lymph node metastases. RESULTS: An increase of Ki-67 immunoreactive cells in ALN compared with that of PTs was observed in 84% of cases (ALN: mean 17%, PTs: mean 8%; p < 0.001), whereas 16% of the cases showed Ki-67 value two to six times lower in the ALNs than in the corresponding PTs (ALN: mean 3.2%, PTs mean 12.5%; p < 0.005). The decrease of Ki-67 positive cells in the ALN was independent from the histotype and the histological grade of the tumor. CONCLUSION: A different cell proliferation fraction between PTs and matching positive ALNs was demonstrated and underlined that the existence of a group of patients with decreased number of Ki-67 immunoreactive cells in lymph node metastases compared with that of the primary tumors could be taken into account in the choice of therapeutic strategy

Thymidylate synthase gene promoter polymorphisms are associated with TSmRNA expressions but not with microsatellite instability in colorectal cancer

Abstract BACKGROUND: Microsatellite instability (MSI) is a biological characteristic of most tumours, being involved in 85% of hereditary non-polyposis colorectal cancer (HNPCC). It also occurs in 10-15% of sporadic colorectal cancers (CRC). HNPCC appears to be caused by germline mutations in mismatch repair (MMR) genes, which are responsible for repairing single base-pair mismatches. MSI is also associated with a better response of CRC to adjuvant chemotherapy with fluoropyrimidines. We investigated any relationship between the MSI status and the TSmRNA expression, the polymorphisms of 5-Fluorouracil (5-FU cellular target, the enzyme thymidylate synthase (TS) and TS expression evaluated by means of immunohistochemistry. MATERIALS AND METHODS: A series of 80 colorectal cancers was evaluated for MSI and polymorphisms in the 3'UTR and the 5'UTR of the TS gene by a PCR assay. TSmRNA was quantified by real-time PCR and the TS expression by immunohistochemical assay. RESULTS: There was no significant association between the polymorphisms in the TS gene and the MSI or between the TSmRNA expression and the MSI status. CRC with a 3R/3R or 2R/3R genotype showed a significantly higher TSmRNA expression than those with the 2R/2R genotype (p = 0.001 and p = 0.028, respectively). Another significant association was found between the TSmRNA expression and the TS immunohistochemical determination (p = < 0.05). No association was found between the polymorphism of the 3'UTR and the TSmRNA expression. CONCLUSION: Our data show that there is no association between MSI status and the polymorphisms in the 3' and 5' UTRs and the TS expression. Tumour samples displaying the 3R/3R or 2R/3R genotype of TS have higher TSmRNA levels than the 2R/2R genotype. Polymorphic variant of the 3'UTR does not influence the TSmRNA level. We found a relationship between the TSmRNA expression, evaluated by real-time PCR, and with the TS level determined by immunohistochemical assay. Thus, genotyping of the 5'UTR and quantification of the TSmRNA expression in human CRC could be considered as predictors for response to SFU-based chemotherapy. The evaluation of the TS expression by means of immunohistochemistry assay remains a safe and reliable assay in CRC

Analisi e progettazione di un sistema di misure quantitative per il monitoraggio dei rischi finanziari delle garanzie di origine.

Lo scopo che si prefigge questo lavoro \ue8 quello di analizzare il mercato emergente delle Garanzie d\u2019Origine (GO), con particolare riferimento alla gestione dei rischi ad esse associati. Malgrado negli ultimi anni i volumi scambiati di queste certificazioni elettroniche abbiano segnato un incremento significativo, i mercati ad esse associati continuano ad essere poco trasparenti ed incompleti, per cui le informazioni e i dati a disposizione risultano essere molto limitati. A questo proposito, in letteratura non esiste quasi nessuno studio di riferimento, n\ue9 tantomeno una specifica normativa per la valutazione del rischio associato a tali strumenti. Questo lavoro suggerisce un possibile approccio alla gestione dei rischi associati alle GO che pu\uf2 costituire un utile riferimento per gli operatori che negoziano tali strumenti. A tal fine saranno presentate diverse tecniche di stima dei rischi di mercato, di liquidit\ue0 e di controparte che non devono essere considerate tra loro alternative, ma parti integranti di un approccio pi\uf9 generale. Poich\ue9 le serie storiche a disposizione sono brevi e caratterizzate da prezzi costanti per lunghi intervalli temporali, si intende proporre metodologie quantitative volte a valutare e gestire, in modo prudenziale, i principali rischi non sempre trattabili con approcci convenzionali

A conservative treatment for eosinophilic cystitis

Introduction: Eosinophilic cystitis is a rare condition which causes common symptoms and may mimic other conditions. Eosinophilic cystitis has several causes such as hypereosinophilic syndrome, inflammatory diseases, neoplasia, parasites or fungal infection, IgE-related diseases, Drug Reaction and Eosinophilia and Systemic Symptoms (DRESS) syndrome, or Churg-Strauss syndrome. Therefore, differential diagnosis is difficult. Case presentation: We report the case of a middle-aged man affected by eosinophilic cystitis with persistent hematuria and other peculiar symptoms that may be brought back to hypereosinophilic crisis. Conclusion: Conservative approach is preferred, avoiding radical cystectomy rather than corticosteroid, antihistaminic and second line therapy. Hyperbaric therapy is an innovative approach for severe relapsing gross hematuria without specific literature and should be studied for further indications

Biological aggressiveness evaluation in prostate carcinomas: Immunohistochemical analysis of PCNA and p53 in a series of Gleason 6 (3+3) adenocarcinomas

We selected 63 prostate tumors with Gleason's grade 6 (3+3), commonly showing both tubular and cribrous patterns. We compared in both patterns the expression of two of the most used biologic markers: PCNA and p53, with the aim to verify the validity of the Gleason's grading system to compare the morphologic grade with biologic aggressiveness and prognostic value. We did not find any statistical difference in the protein immunopositivity, indicating that both patterns could have identical biologic behaviour; then we confirmed the validity of Gleason's system for considering both tubular and cribrous patterns as an intermediate grade of tumoral differentiation. Moreover, we found a linear relationship between the increase of PCNA and the accumulation of mutated p53; this datum could confirm the hypothesis that p53 mutation is a late event in prostate carcinogenesis

Increased expression of transketolase-like-1 in papillary thyroid carcinomas smaller than 1.5 cm in diameter is associated with lymph-node metastases.

BACKGROUND: Patients with small papillary thyroid carcinoma (PTC) may have a high incidence of regional lymph-node (LN) metastases at presentation, and these are considered to be an independent risk factor for tumor recurrence. A mutated transketolase transcript (TKTL1) has been found up-regulated in different human malignancies, and strong TKTL1 protein expression has been associated with aggressiveness and poor patient survival in several epithelial cancers. METHODS: TKTL1 protein expression was analyzed in 256 consecutive cases of PTCs <or=1.5 cm by immunohistochemistry with a specific anti-TKTL1 antibody. RNA analysis was performed by real-time polymerase chain reaction (PCR) in all cases for which frozen material was available, which resulted in 55 fragments of PTC. RESULTS: Increased levels of TKTL1 transcript were detected in 50 of 55 analyzed tumors compared with their corresponding normal tissues. Significant differences in TKTL1 transcript levels were found between cases of PTC with and without LN metastases. In primary tumors, immunoreactivity for TKTL1 was detected in the majority of cases, ranging from 0% to 95.0% (mean, 50.11% +/- 27.75%). A significant association was found between TKTL1 protein expression and the presence of multifocality, bilaterality, extrathyroidal extension, vascular invasion, sclerosis, and LN metastases. In cases with LN metastases, a positive correlation was found between the TKTL1 protein expression in primary tumors and the number of metastatic LNs as well as the diameter of the largest metastatic area in LNs. CONCLUSIONS: These findings suggest that TKTL1 overexpression in PTC <or=1.5 cm may be considered a factor that facilitates tumor growth and progression. (c) 2008 American Cancer Society

Associations between Notch-2, Akt-1 and HER2/neu expression in invasive human breast cancer: a tissue microarray immunophenotypic analysis on 98 patients.

Objective: We aimed to investigate the existence of associations between well-established and newly recognized biological and phenotypic features of breast cancer involved in tumor progression and prognosis. Methods: Ninety-eight cases of invasive breast cancer were assessed for the immunohistochemical expression of estrogen and progesterone receptors, Ki-67, HER2, Akt-1, and Notch-2, using the tissue microarray technique. Data regarding tumor histotype, histological grade, tumor size and lymph node status were collected for each patient and included in the analysis. Results: Several significant associations between histological and/or immunophenotypic features came from the analysis of our data. Positive associations were observed between estrogen and progesterone receptors, tumor grade and proliferation index, tumor grade and HER2, Akt-1 and estrogen receptors, and Notch-2 and HER2. Inverse associations were noted between hormone receptors and tumor grade, hormone receptors and HER2, Akt-1 and tumor grade, and Akt-1 and nodal invasion. Conclusions: Our results, showing the existence of a number of estrogen receptor-positive tumors with Akt-1 expression, better degree of differentiation, and no lymph node involvement, along with the presence of HER2- positive tumors with strong Notch-2 expression, support the role of Notch and Akt in breast cancer progression and suggest that they may also represent new appealing therapeutic targets

RECURRENT RENAL CARCINOMA MIMICKING A GOITRE: A CASE REPORT

Although the thyroid is a high vascularised gland, it is not common terget of metastases from extraglandular cancer. We reported a case of a 70 year-old woman who underwnt total thyroidectomy for multinodular goitre. In the patient's clinical hystory a nephrectomy was carried out 2 years before due to unspecified causes. The histopathological examination of the thyiroid showed a pattern compatible with clear cell renal carcinoma metastasis. The patient's relatives revealed, when questioned again, that the nephrectomy was due to the presence of a clear renal cell carcinoma keep concealed to the patients. Thanks to a timely intervention, the mass was removed and a better survival was guaranted to the patient