Integrating tumor and healthy epithelium in a micro-physiology multi-compartment approach to study renal cell carcinoma pathophysiology

The advent of micro-physiological systems (MPS) in biomedical research has enabled the introduction of more complex and relevant physiological into in vitro models. The recreation of complex morphological features in three-dimensional environments can recapitulate otherwise absent dynamic interactions in conventional models. In this study we developed an advanced in vitro Renal Cell Carcinoma (RCC) that mimics the interplay between healthy and malignant renal tissue. Based on the TissUse Humimic platform our model combines healthy renal proximal tubule epithelial cells (RPTEC) and RCC. Co-culturing reconstructed RPTEC tubules with RCC spheroids in a closed micro-perfused circuit resulted in significant phenotypical changes to the tubules. Expression of immune factors revealed that interleukin-8 (IL-8) and tumor necrosis factor-alfa (TNF-α) were upregulated in the non-malignant cells while neutrophil gelatinase-associated lipocalin (NGAL) was downregulated in both RCC and RPTEC. Metabolic analysis showed that RCC prompted a shift in the energy production of RPTEC tubules, inducing glycolysis, in a metabolic adaptation that likely supports RCC growth and immunogenicity. In contrast, RCC maintained stable metabolic activity, emphasizing their resilience to external factors. RNA-seq and biological process analysis of primary RTPTEC tubules demonstrated that the 3D tubular architecture and MPS conditions reverted cells to a predominant oxidative phosphorylate state, a departure from the glycolytic metabolism observed in 2D culture. This dynamic RCC co-culture model, approximates the physiology of healthy renal tubules to that of RCC, providing new insights into tumor-host interactions. Our approach can show that an RCC-MPS can expand the complexity and scope of pathophysiology and biomarker studies in kidney cancer research.

Microfluidic-based prostate cancer model for investigating the secretion of prostate-specific antigen and microRNAs in vitro

The study of prostate cancer in vitro relies on established cell lines that lack important physiological characteristics, such as proper polarization and expression of relevant biomarkers. Microphysiological systems (MPS) can replicate cancer microenvironments and lead to cellular phenotypic changes that better represent organ physiology in vitro. In this study, we developed an MPS model comprising conventional prostate cancer cells to evaluate their activity under dynamic culture conditions. Androgen-sensitive (LNCaP) and androgen-insensitive (PC3) cells were grown in conventional and 3D cultures, both static and dynamic. Cell morphology, the secretion of prostate-specific antigen, and the expression of key prostate markers and microRNAs were analyzed. LNCaP formed spheroids in 3D and MPS cultures, with morphological changes supported by the upregulation of cytokeratins and adhesion proteins. LNCaP also maintained a constant prostate-specific antigen secretion in MPS. PC3 cells did not develop complex structures in 3D and MPS cultures. PSA expression at the gene level was downregulated in LNCaP-MPS and considerably upregulated in PC3-MPS. MicroRNA expression was altered by the 3D static and dynamic culture, both intra- and extracellularly. MicroRNAs associated with prostate cancer progression were mostly upregulated in LNCaP-MPS. Overall dynamic cell culture substantially altered the morphology and expression of LNCaP cells, arguably augmenting their prostate cancer phenotype. This novel approach demonstrates that microRNA expression in prostate cancer cells is sensitive to external stimuli and that MPS can effectively promote important physiological changes in conventional prostate cancer models.

The Potential Impact of New Drug and Therapeutic Modalities on Drug Resistance to Renal Cell Carcinoma

The treatment of advanced renal cell carcinoma has been substantially improved by the introduction of targeted and immune therapies and their respective combinations. Unleashing the activity of the immune system opened a new and successful front in the fight against cancers. Despite the benefits, drug resistance phenomena and adverse side effects can compromise efficacy. The development of new modalities of drugs and therapies with properties and mechanisms of action that break away from conventional medicines was expanded in recent years. This perspective discusses the prospects of these innovative and highly potent novel treatments in overcoming much of the current issues surrounding the resistance to approved renal cell carcinoma treatments and the challenges facing their introduction.

Influence of the time of occlusion on the quantitative parameters obtained by modelling trans-epidermal water loss curves to describe the human cutaneous barrier function in vivo

Understanding the human cutaneous barrier function is one of the main goals in the study of skin physiology. The plastic occlusion stress test (POST) is a well-known, dynamic approach for studying the barrier, evoking an over-stimulation of the cutaneous water assessed by the trans-epidermal water loss (TEWL) measurement. Rigorous data analysis is imperative, and the compartmental model proposed is particularly suitable for this purpose. It provides a dynamic quantitative description of water mass, but also helps to disclose the relative influence of other factors, such as the time of occlusion. Ten healthy volunteers were submitted to POST studies with different occlusion periods (1 h, 6 h, 12 h and 24 h), allowing the full application of the model to the measured desorption curves. After fitting, the influence of the occlusion time over the evaporation half-lives (t1/2evap) is apparent (t1/2evap ranging from 2.46 min for 1 h of occlusion to 8.53 min for 24 h), increasing with time. Considering the wide applicability of the POST to the study of in vivo cutaneous physiology and pathophysiology, these results demonstrate that the time of occlusion must be considered as a key factor in POST measurements.

Usefulness of blood and urine samples collected on filter paper in detecting cytomegalovirus by the polymerase chain reaction technique

A rapid test for the diagnosis of congenital CMV infection is still needed. This study evaluated the usefulness of dried blood and urine samples collected on filter paper for detecting cytomegalovirus (CMV) by the polymerase chain reaction (PCR) assay compared with the use of liquid urine. Samples were obtained from 332 infants aged 1-7 days. Liquid urine samples were collected into bags, cultured in human fibroblasts, and processed using a multiplex PCR technique. Dried urine samples were obtained by placing a piece of filter paper in contact with the infant's genitals. The heels of neonates were punctured and capillary blood was blotted onto filter paper and dried. Dried blood and urine specimens were analyzed by multiplex PCR and nested-PCR assays. A diagnosis of congenital CMV infection was established by isolating the virus, and by detecting viral DNA in the liquid urine. Of the 332 liquid urine samples collected from 332 neonates, seven (2.1%) were positive for CMV and 325 were negative, by both cell culture and PCR assay. In dried samples, CMV DNA was detectable only with a nested PCR assay. Compared with known CMV infection status, 5/7 (71.4%) neonates were positive for congenital CMV infection using dried blood samples. All 325 uninfected neonates were negative. In the dried urine samples, 4/4 CMV-infected infants gave positive tests, and all 262 uninfected infants were negative. Although further improvements in sample collection and/or processing are still needed, PCR testing on dried urine or blood collected on filter paper is a promising approach in the diagnosis of neonatal CMV infection.

Cyclosporine in the management of corticosteroid-resistant type I autoimmune chronic active hepatitis

Autoimmune chronic active hepatitis is traditionally treated with corticosteroids, or corticosteroids with azathioprine. These drug therapies require long treatment periods and are associated with many debilitating drug side effects. Five patients with type I autoimmune chronic active hepatitis, and one with a probable overlap syndrome were treated with cyclosporine. All patients had previously undergone treatment with corticosteroids or corticosteroids with azathioprine and had failed to achieve total remission. In addition, all patients had significant side effects associated with therapy. Five of six patients normalized or near normalized alanine aminotransferase levels within 10 weeks of starting cyclosporine therapy. Biochemical remission was sustained for periods of up to 1 year in all primary cyclosporine responders as long as therapeutic cyclosporine levels were maintained. All responders had symptomatic improvement. Post-treatment liver biopsy was performed in three patients and histologic improvement was demonstrated in all cases. Cyclosporine appears to be a viable alternative to corticosteroid/azathioprine therapy for autoimmune chronic active hepatitis in patients who experience an incomplete response or who cannot tolerate the side effects of standard therapy.

Failure of colchicine to improve short-term survival in patients with alcoholic hepatitis

Colchicine treatment was used in this randomized placebo-controlled trial in patients with severe acute alcoholic hepatitis [serum bilirubin greater than or equal to 5 mg/dL (85.5 mumol/L) mean, 17.5 +/- 7.5 mg/dL (299.25 +/- 128.25 mumol/L)]. Hospitalization mortality and morbidity and the effect on biochemical test results were the end points of the treatment. Patients in the two groups were evenly matched by demographics and laboratory test results. Mean time to study entry was less than 7 days from admission. The duration of the trial was 30 days. Thirty-six patients (24 men, 12 women) received colchicine (1 mg orally every morning) and 36 (25 men, 11 women) received an identical placebo. Seven (19%) colchicine-treated and six (17%) control patients died during the index hospitalization after a mean of 17.4 +/- 10.8 and 17.8 +/- 5.3 days, respectively (NS). During a 4-month follow-up period from entry into the trial, there were two additional deaths in each group. No differences between placebo- and colchicine-treated patients were observed in any of the laboratory parameters (serum bilirubin, aspartate transaminase, alanine transaminase, prothrombin activity, albumin, white blood cell count, hemoglobin, and creatinine) that were followed up over the 30-day treatment period. The frequency of complications did not differ statistically between the two groups. This study showed no effect of colchicine treatment on mortality and morbidity of severe alcoholic hepatitis. Colchicine cannot be recommended for the treatment of patients with alcoholic hepatitis.

Acute hepatic injury after the withdrawal of immunosuppressive chemotherapy in patients with hepatitis B

Five patients with lymphoproliferative malignancies and chronic hepatitis B suffered severe acute hepatic injury after the withdrawal of multiagent chemotherapy that included high-dose corticosteroid. Four patients died of hepatic failure, three of whom received corticosteroid as treatment for the hepatic injury. We believe that the cause of this entity is massive immune-associated cytolysis of hepatitis B virus infected hepatocytes occurring after a period of immunosuppression and increased viral replication. The literature regarding this complication of chemotherapy and its pathophysiology is reviewed.

Large-volume paracentesis in nonedematous patients with tense ascites: its effect on intravascular volume

In patients with portal hypertension and tense ascites, large-volume paracentesis improves patient comfort and may improve systemic hemodynamics. However, it has been avoided in nonedematous patients because of concern for complications, including intravascular volume depletion. In this study, 12 nonedematous patients with chronic liver disease, portal hypertension and tense ascites underwent 14 large-volume (5-liter) paracenteses for the relief of discomfort and/or respiratory distress. Plasma volume was measured directly by a dilution method with 125I-labeled human serum albumin prior to and at 24 or 48 hr after 13 of the paracenteses. All patients felt better postparacentesis. No dizziness, hypotension, tachycardia, encephalopathy or change in mean serum sodium, creatinine or blood urea nitrogen occurred. Two patients experienced a decrease in hematocrit, which was not explained by blood loss or increase in plasma volume. Mean plasma volume was 3,713 +/- 129 ml (55.1 +/- 1.5 ml per kg ideal body weight) preparacentesis and 3,684 +/- 136 ml postparacentesis, the difference being -0.78% (p = 0.48, NS). Our results suggest that 5-liter paracentesis in nonedematous patients with tense portal hypertension-related ascites improves patient comfort and is not associated with a decrease in measured plasma volume.