Manipulation of the nerve growth factor network in prostate cancer

Autocrine and paracrine events regulated by nerve growth factor (NGF) and relevant receptors (low- and high affinity; p75 neurotrophin receptor [p75(NTR)] and TrkA, respectively) seem to play a significant role in prostate carcinogenesis. Studies reveal that p75(NTR) is both a tumor suppressor of growth and a metastasis suppressor of human prostate cancer cells. Furthermore, p75(NTR) is progressively lost during prostate carcinogenesis. An imbalance between p75(NTR) and tropomyosin receptor kinase A (TrkA)-mediated signals may be involved in the progression of prostate cancer through increased proliferation and reduced apoptosis. The antiproliferative and apoptotic effects of GnRH analogs in prostate cancer cells may be mediated by altering the TrkA:p75(NTR) NGF receptor ratio. Administration of NGF induces a reversion of the androgen-independent/androgen receptor-negative prostate cancer cell lines to a less malignant phenotype. Finally, Trk inhibition is a novel, attractive and rational approach for prostate cancer therapy. This review unravels the NGF 'circuitry' in prostate cancinogenesis for relevant pharmacologic manipulation to lead to the development of novel therapeutic agents.     

Median arcuate ligament syndrome often poses a diagnostic challenge: A literature review with a scope of our own experience

The median arcuate ligament syndrome (MALS) is recognized as a rare clinical entity, characterized by chronic post-prandial abdominal pain, nausea, vomiting, and unintentional weight loss. Due to its vague symptomatology, it is mainly regarded as a diagnosis of exclusion. Patients can often be misdiagnosed for several years before a correct diagnosis is established, also due to a medical team’s clinical suspicion. We present a case series of two patients who suffered from MALS and were treated successfully. The first patient is a 32-year-old woman, presenting with post-prandial abdominal pain and weight loss that have lasted for the past ten years. The second patient, a 50-year-old woman, presented with similar symptomatology, with the symptoms lasting for the last five years. Both cases were treated by laparoscopic division of the median arcuate ligament fibers, which alleviated extrinsic pressure from the celiac artery. Previous cases of MALS were retrieved from PubMed, to assemble a better diagnostic algorithm and propose a treatment method of choice. The literature review suggests an angiography with a respiratory variation protocol as the diagnostic modality of choice, along with the laparoscopic division of the median arcuate ligament fibers as the proposed treatment of choice.     

Serum thyrotropin concentration as a biochemical predictor of thyroid malignancy in patients presenting with thyroid nodules

PURPOSE: Serum thyrotropin (TSH) is a well-established growth factor for thyroid nodules and suppression of TSH concentrations by administering exogenous thyroxine may interfere with the growth of established nodules as well as the formation of new thyroid nodules. The aim of this study was to investigate whether serum TSH at presentation is a predictor of thyroid malignancy in patients with thyroid nodules. METHODS: A total of 565 patients without overt thyroid dysfunction, who presented with palpable thyroid nodule(s) between 1988 and 2004 and underwent at least one fine-needle aspiration biopsy, were retrospectively evaluated. RESULTS: The final diagnostic outcome was established after surgery (n = 122) or after a minimum of 1-year clinical follow-up period. Higher rates of malignancy were observed in patients with serum TSH in the upper tertile of the normal range (P = 0.026). Binary logistic regression analysis revealed significantly increased adjusted odds ratios for the diagnosis of malignancy in patients with serum TSH 1.5-4.0 mIU/l when compared to those with either TSH 0.4-0.8 mIU/l (P = 0.005) or TSH 0.9-1.4 mIU/l (P = 0.007). CONCLUSIONS: The risk of malignancy in thyroid nodules increases in parallel with TSH concentrations within the normal range. TSH concentration at presentation is an independent predictor of thyroid malignancy.     

Are Breast Cancer Molecular Classes Predictive of Survival in Patients with Long Follow-Up?

In this study we investigate the clinical outcomes of 305 breast cancer (BC) patients, aged 55 years or younger, with long follow-up and according to intrinsic subtypes. The cohort included 151 lymph node negative (LN−) and 154 lymph node positive (LN+) patients. Luminal A tumors were mainly LN−, well differentiated, and of stage I; among them AR was an indicator of good prognosis. Luminal B and HER2 positive nonluminal cancers showed higher tumor grade and nodal metastases as well as higher proliferation status and stage. Among luminal tumors, those PR positive and vimentin negative showed a longer survival. HER2-positive nonluminal and TN patients showed a poorer outcome, with BC-specific death mostly occurring within 5 and 10 years. Only luminal tumor patients underwent BC death over 10 years. When patients were divided in to LN− and LN+ no differences in survival were observed in the luminal subgroups. LN− patients have good survival even after 20 years of follow-up (about 75%), while for LN+ patients survival at 20 years (around 40%) was comparable to HER2-positive nonluminal and TN groups. In conclusion, in our experience ER-positive breast tumors are better divided by classical clinical stage than molecular classification, and they need longer clinical follow-up especially in cases with lymph node involvement.