The role of statins in cancer prevention and treatment

Statins inhibit the activity of the rate-limiting enzyme in the cholesterol biosynthetic pathway, HMG-CoA reductase, and are widely prescribed for lowering plasma lipid levels. Several statins have antitumor effects in experimental models, and observational studies suggest that this anticancer activity in the laboratory may translate into effective treatments and/or preventive strategies for certain human cancers. This paper reviews the laboratory and clinical evidence that statins have anticancer activity, discusses the possible mechanisms by which tumor growth may be inhibited by this class of drugs, and outlines strategies for the evaluation of these agents in the prevention and treatment of human cancers.     

Promoter hypermethylation of p16INK4a, E-cadherin, O6-MGMT, DAPK and FHIT in adenocarcinomas of the esophagus, esophagogastric junction and proximal stomach

Although the incidence of Barrett's carcinomas (BC) and proximal gastric adenocarcinomas (PGC) is increasing, little is known about different epigenetic changes in these etiopathogenetically distinct entities. Therefore, 29 adenocarcinomas [10 BC, 7 PGC and 12 tumors of the esophagogastric junction (JC)] and corresponding non-tumor controls (NT) were examined using methylation-specific PCR. The most striking result was a significantly higher promoter methylation frequency of O6-methylguanine methyl transferase (MGMT) in BC compared with JC and PGC (0.7 vs. 0.08 vs. 0.29, respectively; p = 0.011; methylation exclusively in tumors), confirmed immunohistochemically by a significant loss of MGMT protein in BC (p = 0.006). Therefore, MGMT might become a prognosticator and key for chemotherapy with alkylating agents in BC. Frequencies of p16INK4a promoter methylation were 0.5 (BC), 0.42 (JC) and 0.29 (PGC; n.s.), but methylation was almost absent in NT controls. As immunonegative tumors slightly outnumber methylation-positive cases, other mechanisms of gene inactivation must be discussed. Methylation of E-cadherin was rarely observed (1/10 BC, 0/12 JC and 2/7 PGC). This is the first report on promoter methylation of death-associated protein kinase (DAPK) and fragile histidine triad gene (FHIT) in BC; both DAPK (BC 0.7, JC 0.92 and PGC 0.86) and FHIT (BC 0.88, JC 1.0 and PGC 1.0) were found to be highly methylated, suggesting that epigenetic silencing of these tumor suppressors is a common event in adenocarcinomas of the upper gastrointestinal tract, including BC. DAPK (0.54 on average) and FHIT methylation (0.77 on average) were also observed in NT samples. This might constitute an early epigenetic precursor lesion in the normally-appearing tissue surrounding the tumor.     

Hypophosphatemic osteomalacia: a report of five cases and evaluation of bone markers

In this study, we analyzed the changes in biochemical markers of bone turnover in five patients with hypophosphatemic osteomalacia. The following bone markers were evaluated: among bone formation markers, total alkaline phosphatase (TAP), bone alkaline phosphatase (BAP), osteocalcin (bone Gla protein, BGP) and procollagen type I N propeptide (PINP); among bone resorption markers, serum C-terminal cross-linked telopeptide of type I collagen (s-CTx), urinary hydroxyproline (HYP), and N-terminal and and C-terminal cross-linked telopeptides of collagen (NTx and - and -CTx). In addition, the /-CTx ratio was evaluated. TAP and BAP were the markers with the highest increase in both frequency and magnitude. Conversely, BGP values were low in all patients. Collagen-related markers were slightly increased in nearly half of the patients. Among them, PINP showed the highest proportion of increased values. The /-CTx ratio was within normal values in all patients. In conclusion, TAP and BAP seem to be the best bone markers in the diagnostic evaluation of hypophosphatemic osteomalacia. In addition, their high values associated with low levels of BGP provide an even more reliable biochemical profile of this disorder, when associated with the classic mineral and skeletal homeostasis abnormalities.     

Common variable immunodeficiency: experience in Puerto Rico

Common variable immunodeficiency (CVI) is a primary immunodeficiency characterized by hypogammaglobulinemia and an increased susceptibility to infections. The degree and the type of deficiency of serum immunoglobulins, as well as, the clinical course vary from patient to patient, hence the term "variable". The aim of this report is to describe the clinical characteristics and the response to gammaglobulin therapy of a group of patients with CVI followed at the University Hospital of the Puerto Rico Medical Center. To our knowledge, no data on primary immunodeficiencies in Puerto Rico has been reported in the literature. The study group exhibits specific characteristics as compared to other reported series.     

Douching, pelvic inflammatory disease, and incident gonococcal and chlamydial genital infection in a cohort of high-risk women

Douching has been linked to gonococcal or chlamydial cervicitis and pelvic inflammatory disease (PID) in retrospective studies. The authors conducted a 1999-2004 prospective observational study of 1,199 US women who were at high risk of acquiring chlamydia and were followed for up to 4 years. Cervical Neisseria gonorrhoeae and Chlamydia trachomatis were detected from vaginal swabs by nucleic acid amplification. PID was characterized by histologic endometritis or pelvic pain and tenderness plus one of the following: oral temperature >38.3 degrees C, leukorrhea or mucopus, erythrocyte sedimentation rate >15 mm/hour, white blood cell count >10,000, or gonococcal/chlamydial lower genital tract infection. Associations between douching and PID or gonococcal/chlamydial genital infections were assessed by proportional hazards models. The 4-year incidence rate of PID was 10.9% and of gonococcal and/or chlamydial cervicitis was 21.9%. After adjustment for confounding factors, douching two or more times per month at baseline was associated with neither PID (adjusted hazard ratio = 0.76, 95% confidence interval: 0.42, 1.38) nor gonococcal/chlamydial genital infection (adjusted hazard ratio = 1.16, 95% confidence interval: 0.76, 1.78). Frequency of douching immediately preceding PID or gonococcal/chlamydial genital infection was not different between women who developed versus did not develop outcomes. These data do not support an association between douching and development of PID or gonococcal/chlamydial genital infection among predominantly young, African-American women.