Simultaneous inhibition of pan-phosphatidylinositol-3-kinases and MEK as a potential therapeutic strategy in peripheral T-cell lymphomas.

Peripheral T-cell lymphomas are very aggressive hematologic malignancies for which there is no targeted therapy. New, rational approaches are necessary to improve the very poor outcome in these patients. Phosphatidylinositol-3-kinase is one of the most important pathways in cell survival and proliferation. We hypothesized that phosphatidylinositol-3-kinase inhibitors could be rationally selected drugs for treating peripheral T-cell lymphomas. Several phosphatidylinositol-3-kinase isoforms were inhibited genetically (using small interfering RNA) and pharmacologically (with CAL-101 and GDC-0941 compounds) in a panel of six peripheral and cutaneous T-cell lymphoma cell lines. Cell viability was measured by intracellular ATP content; apoptosis and cell cycle changes were checked by flow cytometry. Pharmacodynamic biomarkers were assessed by western blot. The PIK3CD gene, which encodes the δ isoform of phosphatidylinositol-3-kinase, was overexpressed in cell lines and primary samples, and correlated with survival pathways. However, neither genetic nor specific pharmacological inhibition of phosphatidylinositol-3-kinase δ affected cell survival. In contrast, the pan-phosphatidylinositol-3-kinase inhibitor GDC-0941 arrested all T-cell lymphoma cell lines in the G1 phase and induced apoptosis in a subset of them. We identified phospho-GSK3ß and phospho-p70S6K as potential biomarkers of phosphatidylinositol-3-kinase inhibitors. Interestingly, an increase in ERK phosphorylation was observed in some GDC -0941-treated T-cell lymphoma cell lines, suggesting the presence of a combination of phosphatidylinositol-3-kinase and MEK inhibitors. A highly synergistic effect was found between the two inhibitors, with the combination enhancing cell cycle arrest at G0/G1 in all T-cell lymphoma cell lines, and reducing cell viability in primary tumor T cells ex vivo. These results suggest that the combined treatment of pan-phosphatidylinositol-3-kinase + MEK inhibitors could be more effective than single phosphatidylinositol-3-kinase inhibitor treatment, and therefore, that this combination could be of therapeutic value for treating peripheral and cutaneous T-cell lymphomas.

PIM kinases as potential therapeutic targets in a subset of peripheral T cell lymphoma cases.

Currently, there is no efficient therapy for patients with peripheral T cell lymphoma (PTCL). The Proviral Integration site of Moloney murine leukemia virus (PIM) kinases are important mediators of cell survival. We aimed to determine the therapeutic value of PIM kinases because they are overexpressed in PTCL patients, T cell lines and primary tumoral T cells. PIM kinases were inhibited genetically (using small interfering and short hairpin RNAs) and pharmacologically (mainly with the pan-PIM inhibitor (PIMi) ETP-39010) in a panel of 8 PTCL cell lines. Effects on cell viability, apoptosis, cell cycle, key proteins and gene expression were evaluated. Individual inhibition of each of the PIM genes did not affect PTCL cell survival, partially because of a compensatory mechanism among the three PIM genes. In contrast, pharmacological inhibition of all PIM kinases strongly induced apoptosis in all PTCL cell lines, without cell cycle arrest, in part through the induction of DNA damage. Therefore, pan-PIMi synergized with Cisplatin. Importantly, pharmacological inhibition of PIM reduced primary tumoral T cell viability without affecting normal T cells ex vivo. Since anaplastic large cell lymphoma (ALK+ ALCL) cell lines were the most sensitive to the pan-PIMi, we tested the simultaneous inhibition of ALK and PIM kinases and found a strong synergistic effect in ALK+ ALCL cell lines. Our findings suggest that PIM kinase inhibition could be of therapeutic value in a subset of PTCL, especially when combined with ALK inhibitors, and might be clinically beneficial in ALK+ ALCL.

Sentinel lymph node biopsy in selected cases of ductal carcinoma in situ.

INTRODUCTION: Axillary lymphadenectomy is nowadays not recommended to treat ductal carcinoma in situ (DCIS), but there is controversy surrounding the indication for sentinel lymph node biopsy (SLNB). MATERIALS AND METHODS: A prospective study of a selected group of patients diagnosed preoperatively with DCIS was performed between 2004 and 2009. Indications for SLNB were histologically determined high-grade tumours, tumour size >2 cm and patients scheduled to undergo a mastectomy. RESULTS: Sixty-five patients were analysed. Surgical technique was mastectomy in 39 patients (60%) and conservative breast surgery in 26 (40%). Definitive histological study of the resected breast tumour revealed 43 cases (66.2%) of DCIS, 15 (23.1%) of ductal invasive carcinoma and seven (10.7%) microinvasive tumours. In confirmed DCIS, only 6.9% of sentinel lymph nodes were positive, in microinvasive carcinoma 28.5% and in invasive carcinoma 40% were positive. Total number of patients with positive sentinel lymph nodes was 11 (16.9%). Of 39 mastectomies, 12 corresponded to microinvasive or invasive carcinoma and six (50%) showed a positive SLNB. CONCLUSIONS: Performing SLNB avoids an unnecessary second surgery to study axillary lymph nodes in invasive carcinoma diagnosed after definitive histological study. In patients undergoing a mastectomy, this study requires an axillary lymphadenectomy that is not useful in up to 50% of cases. We think that in a selected group of patients with DCIS, SLNB improves tumour staging, adapts the treatment and avoids second surgery in this group of patients.

Prognostic and predictive factors and genetic analysis of early breast cancer.

The great heterogeneity of breast cancer makes it impossible to firmly predict which patients with early-stage tumours will or will not need systemic treatments according to the conventional prognostic factors currently employed. In fact, a substantial percentage of patients receive medical treatment for a disease that will not relapse, while another proportion of patients regarded as having good prognostic factors according to the classic criteria do not receive treatment and suffer disease relapse. Considering that most oncological treatments have short- and long-term toxic effects, new methods capable of offering a more precise prognosis need to be developed. The individualisation of the diagnosis of patients with breast cancer based on molecular and gene expression studies is bringing about a veritable revolution in our understanding of the biology of the disease. The new molecular classification of breast cancer, based on these profiles, allows us to establish a prognosis according to the genetic characteristics of each tumour. Such individualisation of the diagnosis of patients with breast cancer will lead to the application of more specific treatments, thereby improving patient survival with lesser toxicity and increased economic savings. Of the different genetic analytical tests available, MammaPrint has been shown to be the option offering the most information on the behaviour of early breast cancer; as a result, it is the most useful technique in deciding the need for oncological treatment as a complement to surgery.

[Mammary hamartoma]. / Hamartoma mamario.

For many years, mammary hamartoma was considered to be an under-diagnosed disease. However, with the increasing use of diagnostic procedures in breast tumors (mammography, ultrasound, fine needle aspiration cytology and core needle biopsy), diagnosis of this entity has increased. Mammary hamartomas normally manifest as painless, mobile, palpable lumps without adherence to skin or muscle. Mammography shows well-circumscribed tumors, separated from adjacent normal breast tissue. Macroscopically they are well-defined tumors, consisting of benign mammary glandular tissue, fibrous stroma and fat in variable proportions, sometimes with a pseudoencapulation. Because of the lack of cytological and architectural specificity of hamartomas, correlation between clinical manifestations, imaging techniques and histology is essential. This report describes a case of an 11-cm mammary hamartoma in a 46-year-old woman.

Infiltrating ductal carcinoma and ductal carcinoma in situ associated with mammary hamartoma.

Mammary hamartoma is a rare nonmalignant lesion. Only 11 cases of carcinoma associated with hamartoma have been previously described in the literature. We describe a case of infiltrating ductal carcinoma (IDC) and ductal carcinoma in situ (DCIS) associated with hamartoma in a 35-year-old woman. Mammography showed the features of a typical hamartoma with suspicious microcalcifications arising in it. The patient underwent a radical modified mastectomy. It is likely that hamartoma is a coincidental finding. The identification of suspicious microcalcifications in a typical mammographic image of a hamartoma should prompt continued examination to exclude an underlying tumor.

Malignant degeneration of presacral teratoma in the Currarino anomaly.

The autosomal dominant Currarino anomaly (CA) comprises a presacral mass, partial sacral agenesis, and anorectal defects. Chronic constipation in childhood related to anorectal defects is the most common presenting symptom and hemisacrum the most frequent malformation. The presacral mass may be an anterior meningomyelocele, teratoma, hamartoma, dermoid cyst, neuroenteric cyst, or a combination of these. Sepsis and meningitis are frequent serious problems related to the anterior meningomyelocele, whilst malignant transformation of presacral teratoma is a rare, severe complication in CA. Here, we report on a three-generation family segregating the CA, presenting with anorectal defects, severe constipation, and sacral involvement in affected relatives. Teratoma was the most frequent component of the presacral mass. In this kindred a 22-year-old man died of a neuroendocrine tumor, probably related to malignant change in a presacral teratoma. A novel mutation in HLXB9 consisting of a 24-bp deletion and insertion of 2-bp into exon 1, was identified in all patients and in also three asymptomatic members of this family. Anterior meningomyelocele is the most frequently reported component of the presacral masses in CA; however, presacral teratomas carry an inherent risk for malignancy that must be considered in the counseling, surgical treatment options, and follow-up of CA patients.