Histochemistry in the diagnosis of non-neoplastic gastrointestinal disorders

Human Intestinal Defensin 5 Ameliorates the Sensitization of Colonic Cancer Cells to 5-Fluorouracil

BACKGROUND AND AIM

The increasing dilemma of multidrug-resistant cancer cells in response to currently available chemotherapeutic drugs and their associated side effect(s), calls for the investigation of alternative anticancer advances and molecules. Therefore, the present study aimed to elucidate the combinatorial potential against colon cancer of human defensin 5 in combination with 5-fluorouracil (5-FU), and against 5-FU resistant colon tumor cells.

METHODS

The in vivo combinatorial potential of HD-5 with 5-FU was elucidated in terms of tumor morphometrics, apoptosis assay, surface morphology histology of the colon(s), and transcriptional alterations. Changes in membrane dynamics with mucin expression were evaluated by fluorescence microscopy and histochemistry. The in vitro activity of the peptide/drug conjunction was explored by phase contrast microscopy, MTT, LDH assay, and AO/EtBr staining. Chemoresistance to 5-FU was determined by phase contrast microscopy, MTT assay, annexin V-FITC/PI flow cytometry, and MDR-1, Bak, and Bax expression.

RESULTS

In vivo decreases in tumor parameters, with a marked increase in apoptosis and neutrophil infiltrations indicated restoration of normal architecture with improved mucin content in the treated colons. This happened with substantial changes in key molecular markers of the intrinsic apoptotic cascade. Membrane dynamics revealed that peptides and chemotherapeutic drugs could bind to cancerous cells by taking advantage of altered levels of membrane fluidity.

CONCLUSION

Peptide treatment of drug-resistant Caco-2 cells promotes enhanced 5-FU uptake, in contrast to when cells were treated with 5-FU alone. Hence, HD-5 as an adjunct to 5-FU, exhibited strong cancer cell killing even against 5-FU-resistant tumorigenic cells.

Successful use of azithromycin for Escherichia coli-associated renal allograft malakoplakia: a report of two cases

Malakoplakia is a chronic granulomatous disease associated with incomplete clearance of bacterial pathogens. A multimodal approach to therapy includes antimicrobials with intracellular activity, reduction in immunosuppression, and debulking of lesions. Azithromycin has an intracellular mechanism of action and enhanced Gram-negative activity compared to other macrolides. Despite some in vitro data to support its use, there are no clinical breakpoints or epidemiological cut-off values for most Enterobacterales from the European Committee on Antimicrobial Susceptibility Testing (EUCAST) or the Clinical and Laboratory Standards Institute (CLSI). We present two cases, previously unreported, of Escherichia coli associated renal allograft malakoplakia successfully treated with azithromycin.

The Histochemical Alterations of Mucin in Colorectal Carcinoma Quantified by Two Efficient Algorithms of Digital Image Analysis

The practical use of knowledge on the diagnostic-prognostic role of polysaccharide components of mucins in colorectal cancer (CRC) has been difficult, due to the number of histochemical (HC) reaction types, as well as lack of standard methods of computer-assisted analysis of tissue expression of these molecules. Using two algorithms of digital image analysis (by application of Image-Pro Premier and our originally designed program Filter HSV), we evaluated the expression of polysaccharides in tissue samples of CRC patients (n = 33), and fragments of normal colorectal tissue from the same patients (control) using periodic acid Schiff reaction (PAS) (neutral mucins) and alcian blue staining (AB) (acidic mucins). Our results indicate lower expression of the PAS+ and AB+ mucins in CRC, as compared to the control samples. The higher expression of PAS+ polysaccharides was detected in flat tumors than in protruded CRC, while higher AB+ mucins expression was a feature of mucinous CRC subtypes. Positive correlation between mutual PAS+ and AB+ expression, as well as correlations with glucose concentration (PAS+ mucins), and hemoglobin level (AB+ mucins) were observed exclusively in unchanged colorectal samples (control). Both algorithms of digital image analysis (smart segmentation and Filter HSV) work properly and can be used interchangeably in daily practice of pathologists, as useful tools of quantitative evaluation of HC reaction in both normal and cancerous tissues.