Micro-RNAs associated with the evolution of ovarian cancer cisplatin resistance.

OBJECTIVES: Ovarian cancer (OVCA) is the leading cause of mortality among women with gynecologic malignancy, in part due to the development of chemoresistance. We sought to identify micro-RNAs (miRNAs) associated with in vitro development of OVCA chemoresistance that may also represent potential targets for therapy. METHODS: In this study, four OVCA cell lines (A2780CP, A2780S, IGROV1, and OVCAR5) were serially treated with cisplatin in parallel with measurements of miRNA expression changes. RESULTS: Nine miRNAs were found to be associated with increasing cisplatin resistance (IC50) (p<0.01); however, only 5 of these miRNAs have publically available information. Pathway analysis identified 15 molecular signaling pathways that were represented by genes predicted to be targets of the 5 miRNAs (false discovery rate<0.05), 11 of which are associated with the epithelial-mesenchymal transition (EMT). Further analysis identified 2 of those pathways as being associated with overall survival in 218 patients with OVCA. CONCLUSIONS: Collectively, this panel of miRNAs associated with in vitro evolution of OVCA cisplatin resistance and the pathways identified to be associated with EMT and overall patient survival provide a framework for further investigations into EMT as a therapeutic target in patients with OVCA.

Exocrine pancreatic insufficiency and pancreatic exocrine replacement therapy in clinical practice.

Exocrine pancreatic insufficiency (EPI) is a complex condition that disrupts normal digestion and absorption. Patients with EPI may suffer from mild to debilitating malabsorption with a constellation of symptoms that can have a significant effect on quality of life and nutrition status. Pancreatic enzyme replacement therapy (PERT) is effective and safe to treat EPI and is the standard of care for this condition. A wide variety and various forms of these products exist, as well as numerous guidelines and recommendations. Obtaining PERT for patients can oftentimes be cost prohibitive. Determining the presence and extent of EPI can be challenging and patient specific, making it difficult for practitioners. This narrative review will explore these issues, as well as several disease states potentially affected by EPI, and review current management strategies.

The complexity of interactions between female sex hormones and Chlamydia trachomatis infections.

PURPOSE OF REVIEW: This review focuses specifically on the mechanisms by which female sex hormones, estrogen and progesterone, affect Chlamydia trachomatis infections in vivo and in vitro. RECENT FINDINGS: Recent data support previous work indicating that estrogen enhances chlamydial development via multiple mechanisms. Progesterone negatively impacts Chlamydia infections also through multiple mechanisms, particularly by altering the immune response. Conflicting data exist regarding the effect of synthetic hormones, such as those found in hormonal contraceptives, on chlamydial infections. SUMMARY: Numerous studies over the years have indicated that female sex hormones affect C. trachomatis infection. However, we still do not have a clear understanding of how these hormones alter Chlamydia disease transmission and progression. The studies reviewed here indicate that there are many variables that determine the outcome of Chlamydia/hormone interactions, including: 1) the specific hormone, 2) hormone concentration, 3) cell type or area of the genital tract, 4) hormone responsiveness of cell lines, and 5) animal models.

Volume-based feeding improves nutritional adequacy in surgical patients.

BACKGROUND: Critically ill surgical patients often receive inadequate enteral nutrition using traditional rate-based feeding methods. An alternative strategy is volume-based feeding, in which feeding rates are adjusted to deliver a goal volume per day. METHODS: This prospective quality improvement study in a single surgical, trauma, and burn ICU compared volume-based feeding to rate-based feeding in a before-and-after design. Outcomes included calories and protein delivered, length of stay, infection, and mortality. RESULTS: A total of 50 patients received volume-based feeding and 49 rate-based feeding. The volume-based group received a higher proportion of goal calories (84.5% vs. 73.4%; p = 0.005) and protein (86.2% vs. 77.4%; p = 0.01), as well as increased total daily calories (1604 vs. 1356 kcal; p = 0.02). There was no difference in length of stay, mortality, aspiration, or gastrointestinal intolerance. CONCLUSIONS: Volume-based feeding improved nutritional intake in critically ill surgical patients, although this study was underpowered to determine differences in clinical outcomes.

Binding of Elementary Bodies by the Opportunistic Fungal Pathogen Candida albicans or Soluble ß-Glucan, Laminarin, Inhibits Chlamydia trachomatis Infectivity.

Microbial interactions represent an understudied facet of human health and disease. In this study, the interactions that occur between Chlamydia trachomatis and the opportunistic fungal pathogen, Candida albicans were investigated. Candida albicans is a common component of the oral and vaginal microbiota responsible for thrush and vaginal yeast infections. Normally, Candida exist in the body as yeast. However, disruptions to the microbiota create conditions that allow expanded growth of Candida, conversion to the hyphal form, and tissue invasion. Previous studies have shown that a myriad of outcomes can occur when Candida albicans interacts with pathogenic bacteria. To determine if C. trachomatis physically interacts with C. albicans, we incubated chlamydial elementary bodies (EB) in medium alone or with C. albicans yeast or hyphal forms for 1 h. Following incubation, the samples were formaldehyde-fixed and processed for immunofluorescence assays using anti-chlamydial MOMP or anti- chlamydial LPS antibodies. Replicate samples were replenished with culture medium and incubated at 35°C for 0-120 h prior to fixation for immunofluorescence analysis or collection for EB infectivity assays. Data from this study indicates that both C. trachomatis serovar E and C. muridarum EB bind to C. albicans yeast and hyphal forms. This interaction was not blocked by pre-incubation of EB with the Candida cell wall components, mannan or ß-glucans, suggesting that EB interact with a Candida cell wall protein or other structure. Bound EB remained attached to C. albicans for a minimum of 5 days (120 h). Infectivity assays demonstrated that EB bound to C. albicans are infectious immediately following binding (0h). However, once bound to C. albicans, EB infectivity decreased at a faster rate than EB in medium alone. At 6h post binding, 40% of EB incubated in medium alone remained infectious compared to only 16% of EB bound to C. albicans. Likewise, pre-incubation of EB with laminarin, a soluble preparation of ß-glucan, alone or in combination with other fungal cell wall components significantly decreases chlamydial infectivity in HeLa cells. These data indicate that interactions between EB and C. albicans inhibit chlamydial infectivity, possibly by physically blocking EB interactions with host cell receptors.

The Chinese herb polyphyllin D sensitizes ovarian cancer cells to cisplatin-induced growth arrest.

PURPOSE: We evaluated the effects of polyphyllin D (PD), a natural compound with anti-neoplastic activity and a major component of the Chinese herb Paris polyphylla, on ovarian cancer (OVCA) cell line proliferation and platinum sensitivity. METHODS: A panel of 20 OVCA cell lines was subjected to PD treatment, MTS proliferation assays, and determination of IC50. Pre-treatment, baseline genome-wide Affymetrix expression analysis was performed on each cell line, and Pearson's correlation was performed to identify genes associated with OVCA PD sensitivity. Twelve cell lines were treated with PD with and without cisplatin, and the effects of PD on cisplatin IC50 were quantified. Genes associated with OVCA PD sensitivity were evaluated for associations with survival in a publically available clinico-genomic dataset of 218 patients with OVCA. RESULTS: Our results showed that PD exhibited anti-proliferative effects against all OVCA cell lines tested, with IC50 values ranging from 0.2 to 1.4 µm. Furthermore, in all cell lines, PD treatment significantly decreased cisplatin IC50 (mean IC50 reduction of 2.1 µm; P < 0.02). Pearson's correlation test identified 25 probe sets, representing 18 unique genes to be associated with PD sensitivity (FDR = 0). We found that one of these genes was associated with overall survival in women with OVCA: CLDN4 (P = 0.014). CONCLUSION: Our findings highlight the value of PD as a natural product with anti-cancer properties, which may also enhance the activity of existing therapeutic agents.

BAD-mediated apoptotic pathway is associated with human cancer development.

The malignant transformation of normal cells is caused in part by aberrant gene expression disrupting the regulation of cell proliferation, apoptosis, senescence and DNA repair. Evidence suggests that the Bcl-2 antagonist of cell death (BAD)-mediated apoptotic pathway influences cancer chemoresistance. In the present study, we explored the role of the BAD-mediated apoptotic pathway in the development and progression of cancer. Using principal component analysis to derive a numeric score representing pathway expression, we evaluated clinico-genomic datasets (n=427) from corresponding normal, pre-invasive and invasive cancers of different types, such as ovarian, endometrial, breast and colon cancers in order to determine the associations between the BAD-mediated apoptotic pathway and cancer development. Immunofluorescence was used to compare the expression levels of phosphorylated BAD [pBAD (serine-112, -136 and -155)] in immortalized normal and invasive ovarian, colon and breast cancer cells. The expression of the BAD-mediated apoptotic pathway phosphatase, PP2C, was evaluated by RT-qPCR in the normal and ovarian cancer tissue samples. The growth-promoting effects of pBAD protein levels in the immortalized normal and cancer cells were assessed using siRNA depletion experiments with MTS assays. The expression of the BAD-mediated apoptotic pathway was associated with the development and/or progression of ovarian (n=106, p<0.001), breast (n=185, p<0.0008; n=61, p=0.04), colon (n=22, p<0.001) and endometrial (n=33, p<0.001) cancers, as well as with ovarian endometriosis (n=20, p<0.001). Higher pBAD protein levels were observed in the cancer cells compared to the immortalized normal cells, whereas PP2C gene expression was lower in the cancer compared to the ovarian tumor tissue samples (n=76, p<0.001). The increased pBAD protein levels after the depletion of PP2C conferred a growth advantage to the immortalized normal and cancer cells. The BAD-mediated apoptotic pathway is thus associated with the development of human cancers likely influenced by the protein levels of pBAD.

Pancreatic enzyme replacement therapy during pancreatic insufficiency.

Pancreatic stimulation and therefore digestion is a tightly controlled and hormonally mediated process. Any alterations affecting any of the systematic steps for successful digestion and absorption to occur will impair appropriate pancreatic enzymatic secretion, entry into the bowel lumen, functionality once inside the lumen, and thus appropriate mixing with foods and nutrients. Many causes of pancreatic insufficiency may require the initiation of pancreatic enzyme therapy, including but not limited to cystic fibrosis, pancreatic cancer, acute and chronic pancreatitis, and pancreatic surgery. This purpose of this article is to help clarify the conditions that cause pancreatic insufficiency, how to determine if the patient is malabsorbing, and the best use of pancreatic enzyme replacement therapy for treatment in these conditions. The first step in determining if pancreatic enzyme therapy is appropriate is to determine if the patient is malabsorbing specifically due to pancreatic exocrine insufficiency. An overview of the methods used to determine pancreatic insufficiency is provided, as well as appropriate treatment methods. Recent Food and Drug Administration regulations require a more thorough process, including randomized controlled trials to prove the safety and efficacy of pancreatic enzymes, to approve them for use. The studies used to verify efficacy also are examined. Last, dosing guidelines and some unconventional ways to administer pancreatic enzymes, such as during enteral feedings, are reviewed.

Pancreatic surgery: indications, complications, and implications for nutrition intervention.

Pancreatic surgery is a complicated procedure leaving postoperative patients with an altered gastrointestinal (GI) anatomy and a potential for further surgical complications such as leaks and fistulas. Beyond surgical complications, these patients are prone to delayed gastric emptying, fat malabsorption, and hyperglycemia, with early satiety and poor appetite further compromising nutrition status. Many of these patients are malnourished prior to this major surgical procedure, and significant weight loss is common postoperatively. Does this affect their outcome? There seems to be a lack of consensus in this patient population regarding how to optimize nutrition and limit potential deleterious effects of this surgery. It is important to first understand the underlying disease condition and the effects to the gland, different forms of surgery with subsequent GI alterations, and common surgical and digestive complications. Once this is reviewed, existing nutrition support literature will be explored in attempts to determine the best nutrition management in this patient population.

Suspected neuroleptic malignant syndrome during quetiapine-clozapine cross-titration.

Neuroleptic malignant syndrome (NMS) is a physiologic phenomenon that has been associated with the use of both first- and second-generation antipsychotics resultant to their ability to block dopamine blockade in the basal ganglia and hypothalamic regions of the brain. The typical reaction involves the presentation of muscle rigidity, changes in mental status, temperature elevation, labile blood pressure, and elevations in creatinine kinase and white blood cell counts. The reaction is most often reported early in the course of therapy but is well documented to have the potential to occur at any point in time. Untreated NMS can be fatal, often from secondary causes such as deep venous thrombosis and pulmonary embolism. Treatment involves immediate discontinuation of the offending agent, supportive therapy of clinical symptoms, and may include the use of the skeletal muscle relaxant, dantrolene sodium, or the dopaminergic agents bromocriptine or amantadine. In this case, we present a patient who developed symptoms of NMS during the cross-taper and conversion from quetiapine to clozapine. The patient was treated for NMS; however, his clinical diagnosis was never able to be definitively determined as he was initially evaluated for septicemia and later treated for suspected bacterial infection with antibiotics, and clozapine-associated side effects cannot be ruled-out as a contributing source to the clinical presentation. The estimated Naranjo Scale score for this case report is 3.