Automated interpretation of time-lapse quantitative phase image by machine learning to study cellular dynamics during epithelial-mesenchymal transition

SIGNIFICANCE

Machine learning is increasingly being applied to the classification of microscopic data. In order to detect some complex and dynamic cellular processes, time-resolved live-cell imaging might be necessary. Incorporating the temporal information into the classification process may allow for a better and more specific classification.

AIM

We propose a methodology for cell classification based on the time-lapse quantitative phase images (QPIs) gained by digital holographic microscopy (DHM) with the goal of increasing performance of classification of dynamic cellular processes.

APPROACH

The methodology was demonstrated by studying epithelial-mesenchymal transition (EMT) which entails major and distinct time-dependent morphological changes. The time-lapse QPIs of EMT were obtained over a 48-h period and specific novel features representing the dynamic cell behavior were extracted. The two distinct end-state phenotypes were classified by several supervised machine learning algorithms and the results were compared with the classification performed on single-time-point images.

RESULTS

In comparison to the single-time-point approach, our data suggest the incorporation of temporal information into the classification of cell phenotypes during EMT improves performance by nearly 9% in terms of accuracy, and further indicate the potential of DHM to monitor cellular morphological changes.

CONCLUSIONS

Proposed approach based on the time-lapse images gained by DHM could improve the monitoring of live cell behavior in an automated fashion and could be further developed into a tool for high-throughput automated analysis of unique cell behavior.

Chk1 inhibition significantly potentiates activity of nucleoside analogs in TP53-mutated B-lymphoid cells

Treatment options for TP53-mutated lymphoid tumors are very limited. In experimental models, TP53-mutated lymphomas were sensitive to direct inhibition of checkpoint kinase 1 (Chk1), a pivotal regulator of replication. We initially tested the potential of the highly specific Chk1 inhibitor SCH900776 to synergize with nucleoside analogs (NAs) fludarabine, cytarabine and gemcitabine in cell lines derived from B-cell malignancies. In p53-proficient NALM-6 cells, SCH900776 added to NAs enhanced signaling towards Chk1 (pSer317/pSer345), effectively blocked Chk1 activation (Ser296 autophosphorylation), increased replication stress (p53 and γ-H2AX accumulation) and temporarily potentiated apoptosis. In p53-defective MEC-1 cell line representing adverse chronic lymphocytic leukemia (CLL), Chk1 inhibition together with NAs led to enhanced and sustained replication stress and significantly potentiated apoptosis. Altogether, among 17 tested cell lines SCH900776 sensitized four of them to all three NAs. Focusing further on MEC-1 and co-treatment of SCH900776 with fludarabine, we disclosed chromosome pulverization in cells undergoing aberrant mitoses. SCH900776 also increased the effect of fludarabine in a proportion of primary CLL samples treated with pro-proliferative stimuli, including those with TP53 disruption. Finally, we observed a fludarabine potentiation by SCH900776 in a T-cell leukemia 1 (TCL1)-driven mouse model of CLL. Collectively, we have substantiated the significant potential of Chk1 inhibition in B-lymphoid cells.

Automated classification of cell morphology by coherence-controlled holographic microscopy

In the last few years, classification of cells by machine learning has become frequently used in biology. However, most of the approaches are based on morphometric (MO) features, which are not quantitative in terms of cell mass. This may result in poor classification accuracy. Here, we study the potential contribution of coherence-controlled holographic microscopy enabling quantitative phase imaging for the classification of cell morphologies. We compare our approach with the commonly used method based on MO features. We tested both classification approaches in an experiment with nutritionally deprived cancer tissue cells, while employing several supervised machine learning algorithms. Most of the classifiers provided higher performance when quantitative phase features were employed. Based on the results, it can be concluded that the quantitative phase features played an important role in improving the performance of the classification. The methodology could be valuable help in refining the monitoring of live cells in an automated fashion. We believe that coherence-controlled holographic microscopy, as a tool for quantitative phase imaging, offers all preconditions for the accurate automated analysis of live cell behavior while enabling noninvasive label-free imaging with sufficient contrast and high-spatiotemporal phase sensitivity.

Local application of adipose-derived mesenchymal stem cells supports the healing of fistula: prospective randomised study on rat model of fistulising Crohn's disease

OBJECTIVE

Local application of adipose-derived mesenchymal stem cells (ADSC) represents a novel approach for the management of perianal fistula in patients with Crohn's disease. A randomised study on an animal model was performed to investigate the efficacy and to detect the distribution of implanted ADSCs by bioluminescence (BLI).

MATERIALS AND METHODS

A caecostomy was used as a fistula model in 32 Lewis rats. The ADSCs were isolated from transgenic donor expressing firefly luciferase. Animals were randomly assigned to groups given injections of 4 × 10⁶ cells (n = 16, group A) or placebo (n = 16, group B) in the perifistular tissue. Fistula drainage assessment was used to evaluate the fistula healing. After application of D-luciferin, cell viability and distribution was detected using an IVIS Lumina XR camera on days 0, 2, 7, 14 and 30.

RESULTS

The fistula was identified as healed in 6 (38%) animals in group A vs. 1 case (6.3%) in group B (p = .033). The BLI was strongest immediately after administration of ADSCs 31.2 × 10⁴ (6.09-111 × 10⁴) p/s/cm²/sr. The fastest decrease was observed within the first 2 days when values fell by 50.2%. The BLI 30 days after injection was significantly higher in animals with healed fistulas - 8.23 × 10⁴ (1.18-16.9 × 10⁴) vs. 1.74 × 10⁴ (0.156-6.88 × 10⁴); p = .0393.

CONCLUSIONS

Local application of ADSCs resulted in significantly higher fistula closure rate on an animal model. BLI monitoring was proved to be feasible and showed rapid reduction of the ADSC mass after application. More viable cells were detected in animals with healed fistula at the end of the follow-up.

Liposomal Doxorubicin Combined with Regional Hyperthermia: Reducing Systemic Toxicity and Improving Locoregional Efficacy in the Treatment of Solid Tumors

Incorporation of doxorubicin into polyethylene glycol-coated (pegylated) liposomes increases the therapeutic index, prolongs circulation time and enhances tumor localization. Pegylated liposomal doxorubicin (PLD) is an established therapeutic agent in epithelial ovarian carcinoma (EOC), breast carcinoma or Kaposi's sarcoma, and PLD administration results in reduction of toxicity. Addition of regional hyperthermia increases liposome extravasation, induces the doxorubicin release from the liposomes, and the combination of hyperthermia and doxorubicin itself may be supra-additive, resulting in enhanced antitumor efficacy in the heated region. Encouraging results have been reported for the combination of PLD and hyperthermia in EOC, breast carcinoma and hepatocellular carcinoma.

Rabbit antithymocyte globulin-induced serum sickness disease and human kidney graft survival

BACKGROUND

Rabbit-generated antithymocyte globulins (ATGs), which target human T cells, are widely used as immunosuppressive agents during treatment of kidney allograft recipients. However, ATGs can induce immune complex diseases, including serum sickness disease (SSD). Rabbit and human IgGs have various antigenic differences, including expression of the sialic acid Neu5Gc and α-1-3-Gal (Gal), which are not synthesized by human beings. Moreover, anti-Neu5Gc antibodies have been shown to preexist and be elicited by immunization in human subjects. This study aimed to assess the effect of SSD on long-term kidney allograft outcome and to compare the immunization status of grafted patients presenting with SSD following ATG induction treatment.

METHODS

We analyzed data from a cohort of 889 first kidney graft recipients with ATG induction (86 with SSD [SSD(+)] and 803 without SSD [SSD(-)]) from the Données Informatisées et Validées en Transplantation data bank. Two subgroups of SSD(+) and SSD(-) patients that had received ATG induction treatment were then assessed for total anti-ATG, anti-Neu5Gc, and anti-Gal antibodies using ELISA assays on sera before and after transplantation.

RESULTS

SSD was significantly associated with long-term graft loss (>10 years, P = 0.02). Moreover, SSD(+) patients exhibited significantly elevated titers of anti-ATG (P = 0.043) and anti-Neu5Gc (P = 0.007) IgGs in late post-graft samples compared with SSD(-) recipients.

CONCLUSION

In conclusion, our data indicate that SSD is a major contributing factor of late graft loss following ATG induction and that anti-Neu5Gc antibodies increase over time in SSD(+) patients.

FUNDING

This study was funded by Société d'Accélération du Transfert de Technologies Ouest Valorisation, the European FP7 "Translink" research program, the French National Agency of Research, Labex Transplantex, the Natural Science and Engineering Research Council of Canada, and the Canadian Foundation for Innovation.

Estimated Glomerular Filtration Rate in Oncology Patients before Cisplatin Chemotherapy

BACKGROUND

The aim of the study is to compare measured glomerular filtration rate by technetium radiolabled diethylene tiamine pentaacetic acid (mGFR DTPA) to estimated GFR (eGFR). Glomerular filtration rate (GFR) is estimated from serum creatinine (eGFRcreatinine), serum cystatin C (eGFRcystatin C) and by combined equation (eGFRcreatinine+cystatin C). This study focuses on oncology patients considered for treatment with cisdiamminedichloroplatinum (cisplatin). We evaluated the impact of different GFR methods on the reduction of cisplatin dose.

PATIENTS AND METHODS

The study population consisted of 112 consecutive oncology patients from oncology center treated in the town of Zlin in the Czech Republic, who were considered for cisplatin treatment. mGFR DTPA was performed by dynamic renal 99mTc scintigraphy method using diethyltriaminepentaacetic acid. Creatinine and cystatin C were determined by newly standardized tests. Estimation of GFR was calculated using The Chronic Kidney Disease Epidemiology (CKD EPI) equations which were established in 2009 and 2012.

RESULTS

The median (interquartile range) of mGFR DTPA was 1.335 ml/s/1.73 m2 (1.070-1.725). The median of eGFRcystatin C 1.195 ml/s/1.73 m2 (0.885-1.625) was lower than mGFR DTPA (p<0.05). The median of eGFRcreatinine 1.460 ml/s/1.73 m2 (1.210-1.660) was higher than mGFR DTPA (p<0.05). Correlation analysis and Bland Altman plots show high individual differences between mGFR DTPA and all eGFRs.

CONCLUSIONS

Oncology patients are a very special group of patients who dif-fer from general population. There are significant individual differences between mGFR DTPA and all eGFRs, impacting detection rate of CKD and potential drug dosage adjustment.

Quantitative phase imaging through scattering media by means of coherence-controlled holographic microscope

A coherence-controlled holographic microscope (CCHM) enables quantitative phase imaging with coherent as well as incoherent illumination. The low spatially coherent light induces a coherence gating effect, which makes observation of samples possible also through scattering media. The paper describes theoretically and simulates numerically imaging of a two-dimensional object through a static scattering layer by means of CCHM, with the main focus on the quantitative phase imaging quality. The authors have investigated both strongly and weakly scattering media characterized by different amounts of ballistic and diffuse light. It is demonstrated that the phase information can be revealed also for the case of the static, strongly scattering layer. The dependence of the quality of imaging process on the spatial light coherence is demonstrated. The theoretical calculations and numerical simulations are supported by experimental data gained with a model phase object, as well as living carcinoma cells treated in an optically turbid emulsion.

Dynamic phase differences based on quantitative phase imaging for the objective evaluation of cell behavior

Quantitative phase imaging (QPI) brought innovation to noninvasive observation of live cell dynamics seen as cell behavior. Unlike the Zernike phase contrast or differential interference contrast, QPI provides quantitative information about cell dry mass distribution. We used such data for objective evaluation of live cell behavioral dynamics by the advanced method of dynamic phase differences (DPDs). The DPDs method is considered a rational instrument offered by QPI. By subtracting the antecedent from the subsequent image in a time-lapse series, only the changes in mass distribution in the cell are detected. The result is either visualized as a two dimensional color-coded projection of these two states of the cell or as a time dependence of changes quantified in picograms. Then in a series of time-lapse recordings, the chain of cell mass distribution changes that would otherwise escape attention is revealed. Consequently, new salient features of live cell behavior should emerge. Construction of the DPDs method and results exhibiting the approach are presented. Advantage of the DPDs application is demonstrated on cells exposed to an osmotic challenge. For time-lapse acquisition of quantitative phase images, the recently developed coherence-controlled holographic microscope was employed.

Coherence-controlled holographic microscopy enabled recognition of necrosis as the mechanism of cancer cells death after exposure to cytopathic turbid emulsion

Coherence-controlled holographic microscopy (CCHM) in low-coherence mode possesses a pronounced coherence gate effect. This offers an option to investigate the details of cellular events leading to cell death caused by cytopathic turbid emulsions. CCHM capacity was first assessed in model situations that showed clear images obtained with low coherence of illumination but not with high coherence of illumination. Then, the form of death of human cancer cells induced by treatment with biologically active phospholipids (BAPs) preparation was investigated. The observed overall retraction of cell colony was apparently caused by the release of cell-to-substratum contacts. This was followed by the accumulation of granules decorating the nuclear membrane. Then, the occurrence of nuclear membrane indentations signaled the start of damage to the integrity of the cell nucleus. In the final stage, cells shrunk and disintegrated. This indicated that BAPs cause cell death by necrosis and not apoptosis. An intriguing option of checking the fate of cancer cells caused by the anticipated cooperative effect after adding another tested substance sodium dichloroacetate to turbid emulsion is discussed on grounds of pilot experiments. Such observations should reveal the impact and mechanism of action of the interacting drugs on cell behavior and fate that would otherwise remain hidden in turbid milieu.

Comparison of Cross-linked and Non-Cross-linked Acellular Porcine Dermal Scaffolds for Long-term Full-Thickness Hernia Repair in a Small Animal Model

BACKGROUND

This study compared the strength of incorporation and biocompatibility of 2 porcine-derived grafts (cross-linked and non-cross-linked) in a rat hernia model.

METHODS

A standardized 2 × 4 cm(2) fascial defect was created in 30 Wistar rats and repaired with either a cross-linked or a non-cross-linked graft. The rats were killed 3, 6, and 12 months later. The strength of incorporation, vascularization, cellular invasion, foreign body reaction, and capsule formation were evaluated.

RESULTS

Both graft materials showed cellular ingrowth and neovascularization by 3 months postimplantation. The average level of cellularization was significantly higher in the non-cross-linked grafts than in the cross-linked grafts at 6 months (2 vs 1; P = .029). Vascularization was significantly higher in the non-cross-linked grafts than in the cross-linked grafts at 6 months postimplantation (2 vs 1; P = .029) and insignificant at 3 months (2 vs 1.75; P = .311) and 12 months (1 vs 0.67; P = 1). The maximum load and breaking strength of both biomaterials increased during the study period. Overall, the strength of incorporation of the non-cross-linked grafts increased from 3 months (0.75 MPa) to 12 months (3.06 MPa) postimplantation. The strength of incorporation of the cross-linked grafts also increased from 3 months (0.59 MPa) to 12 months (1.58 MPa) postimplantation.

CONCLUSIONS

The results of our study suggest that non-cross-linked grafts may be slightly more biocompatible and allow a more rapid and higher degree of cellular penetration and vascularization, resulting in stronger attachment to the tissues.

Long-term IgG response to porcine Neu5Gc antigens without transmission of PERV in burn patients treated with porcine skin xenografts

Acellular materials of xenogenic origin are used worldwide as xenografts, and phase I trials of viable pig pancreatic islets are currently being performed. However, limited information is available on transmission of porcine endogenous retrovirus (PERV) after xenotransplantation and on the long-term immune response of recipients to xenoantigens. We analyzed the blood of burn patients who had received living pig-skin dressings for up to 8 wk for the presence of PERV as well as for the level and nature of their long term (maximum, 34 y) immune response against pig Ags. Although no evidence of PERV genomic material or anti-PERV Ab response was found, we observed a moderate increase in anti-αGal Abs and a high and sustained anti-non-αGal IgG response in those patients. Abs against the nonhuman sialic acid Neu5Gc constituted the anti-non-αGal response with the recognition pattern on a sialoglycan array differing from that of burn patients treated without pig skin. These data suggest that anti-Neu5Gc Abs represent a barrier for long-term acceptance of porcine xenografts. Because anti-Neu5Gc Abs can promote chronic inflammation, the long-term safety of living and acellular pig tissue implants in recipients warrants further evaluation.

Antibiotic susceptibility and resistance of Staphylococcus aureus isolated from fresh porcine skin xenografts: risk to recipients with thermal injury

The previous use of fresh porcine xenografts at the Prague Burn Centre had raised concerns over the transmission of zoonotic pathogens. This study examines the risk of zoonotic Staphylococcus aureus colonisation of burn patients from fresh porcine skin xenografts. Samples were collected from the nares, skin and perineum of commercial pigs (n=101) and were screened for methicillin sensitive S. aureus (MSSA) and resistant S. aureus (MRSA). The efficacy of the antibiotic wash used in decontamination of the pigskin was tested against planktonic- and biofilm-grown isolates. The spa type of each isolate was also confirmed. All pig swabs were negative for MRSA but 86% positive for MSSA. All planktonic-grown isolates of MSSA were sensitive to chloramphenicol and nitrofurantoin and 44% of isolates were resistant to streptomycin. Isolates grown as biofilm exhibited higher rates of antimicrobial resistance. Sequence analysis revealed three distinct spa types of the MRSA ST398 clonal type. This finding demonstrates the existence of a MSSA reservoir containing spa types resembling those of well-known MRSA strains. These MSSA exhibit resistance to antibiotics used for decontamination of the pigskin prior to xenograft. Amended use of procurement could allow the use of fresh pigskin xenografts to be reinstated.

Neoplastic progression of the human breast cancer cell line G3S1 is associated with elevation of cytoskeletal dynamics and upregulation of MT1-MMP

The newly established breast cancer cell line G3S1, derived from EM-G3 breast cancer progenitors, was analyzed for functional changes related to neoplastic progression manifested by elevated invasiveness and enhanced capability to degrade gelatin. Degradation of gelatin and invasiveness of G3S1 cells was found to be dependent on the activity of matrix proteinases and actin cytoskeletal dynamics. Therefore, the expression and activity of these proteases was compared in G3S1 and EM-G3 cells. Despite enhanced capability of G3S1 cells to degrade gelatin, these cells exhibited lower levels of secreted extracellular matrix degrading proteases than parental EM-G3 cells. However, the expression of membrane-bound MT1-MMP was strongly elevated in G3S1 cells. While the degradation of gelatin was associated with invadopodia-like structures in both EM-G3 and G3S1 cells, the cytoskeletal remodeling dynamics was greatly elevated in G3S1 cells, suggesting that upregulation of MT1-MMP, together with elevation of cytoskeletal remodeling dynamics can effectively cause elevated invasiveness and enhanced matrix degrading capability in G3S1 cells.

Proving tumour cells by acute nutritional/energy deprivation as a survival threat: a task for microscopy

Malignant cells appear to possess a special aptitude for survival. We attempted to prove this in vitro by acute nutritional and energy deprivation as a survival threat. A phosphate-buffered saline (PBS) survival test in cell culture allowed static observations. These were supplemented by classic and quantitative phase-contrast time-lapse microscopy. From one normal and four neoplastic cell populations, no cells survived 77 hours of exposure to PBS. Only G3S2 derived from a human breast carcinoma survived 60 hours. Cells in sparse culture were more vulnerable than those in dense. Epithelial cells were more vigorous than mesenchymal cells. Cells of greater malignancy resisted longer. Evaluation in culture as detailed by digital holographic microscopy (DHM) revealed an increase in the compactness of the intracellular mass motility from normal to metastasizing mesenchymal cells, thus reaching the level of epithelial G3S2 cells. Studying the PBS survival test with DHM opens a new approach to investigations of the structural integrity of neoplastic cells.

Up-regulation of Rho/ROCK signaling in sarcoma cells drives invasion and increased generation of protrusive forces

Tumor cell invasion is the most critical step of metastasis. Determination of the mode of invasion within the particular tumor is critical for effective cancer treatment. Protease-independent amoeboid mode of invasion has been described in carcinoma cells and more recently in sarcoma cells on treatment with protease inhibitors. To analyze invasive behavior, we compared highly metastatic sarcoma cells with parental nonmetastatic cells. The metastatic cells exhibited a functional up-regulation of Rho/ROCK signaling and, similarly to carcinoma cells, an amoeboid mode of invasion. Using confocal and traction force microscopy, we showed that an up-regulation of Rho/ROCK signaling leads to increased cytoskeletal dynamics, myosin light chain localization, and increased tractions at the leading edge of the cells and that all of these contributed to increased cell invasiveness in a three-dimensional collagen matrix. We conclude that cells of mesenchymal origin can use the amoeboid nonmesenchymal mode of invasion as their primary invading mechanism and show the dependence of ROCK-mediated amoeboid mode of invasion on the increased capacity of cells to generate force.

Is there a qualitative interaction between adjuvant trastuzumab and size of the primary tumor in breast cancer?

Benefit of adjuvant trastuzumab in breast cancer has been reported in four randomized trials of phase III, and these results are consistent in showing improvement in disease-free survival (DFS). Current evidence for homogeneity of this DFS benefit in subgroups of patients with the different size of the primary HER2-positive tumor treated according to the HERA trial is reviewed. It is evident that current published evidence is insufficient to rule out that there is a cohort of patients with HER2-positive disease who do not achieve a reduction in the risk of recurrence by adjuvant treatment with trastuzumab after completion of previous adjuvant chemo- and radiotherapy. An alternative interpretation of results of the HERA trial currently available in two primary reports (1-year, and 2-year median follow- up, respectively) is discussed. The risk factors of central nervous system (CNS) metastases in breast cancer and problem of CNS metastases in HER2-positive tumors are briefly reviewed. A hypothesis on the relations between brain metastases, their risk factors, the size of the primary tumor, and their impact on the DFS in patients with HER2-positive tumors treated with adjuvant trastuzumab is proposed based on the results of the HERA trial. Altogether, some direct evidence is presented here based on the published results of the HERA trial, and still more indirect evidence based on the information on related topics in literature, to show that current clinical practice of adjuvant trastuzumab in mono-therapy, which is based on assumption that there is a homogeneous benefit as for disease-free survival for all sizes of primary HER2-positive tumors above 1 cm, may not be based on such firm evidence as is commonly presented.

A simple non-destructive test of cellular activity (NTCA) for in vitro assessment of cancer cell chemosensitivity/resistance

Determination of chemosensitivity/chemoresistance is becoming increasingly important for individualization of breast cancer chemotherapy. We developed a simple non-destructive test of cellular activity (NTCA) for assessment of the cytopathic effect of antitumour drugs in vitro. Contrary to routinely used methods (e.g. MTT), besides the comparative evaluation of metabolic activity using pH (given by the medium colour), the NTCA enables the simultaneous assessment of proliferation and morphology of cultured cells (phase-contrast microscopy) at any time during the incubation with cytostatics. Moreover, the regenerative potential of the cells can be examined by cell recovery and growth after drug removal. We provide evidence for the relevance of NTCA in chemosensitivity testing of primary breast cancer cells and breast cancer cell lines for cisplatin, gemcitabine and tamoxifen. NTCA represents a simple addition to the chemosensitivity assessment and could also serve for rapid screening of new antitumour strategies.

Systemic Immune Activation and Peripheral Blood Lymphocytes during Primary Chemotherapy with the Combination of Doxorubicin and Paclitaxel in Patients with Breast Carcinoma

In recent years, there has been interest in the study of alterations of the immune system of breast carcinoma patients undergoing primary chemotherapy. Changes in the phenotype, function of peripheral blood lymphocytes as well as alterations in the release of pro-inflammatory cytokines accompanying the administration of primary chemotherapy have been described. We have investigated urinary neopterin and peripheral blood leukocyte phenotype in 44 breast carcinoma patients treated with the combination of doxorubicin and paclitaxel.

Compared to controls, patients with breast carcinoma had significantly lower relative number of CD3+ lymphocytes, and significantly higher relative and absolute numbers of natural killer cells, relative and absolute numbers of CD3+DR+ lymphocytes, relative and absolute numbers of CD3+CD69+ lymphocytes, relative numbers of CD8+CD57+ lymphocytes and CD14+DR+ monocytes and relative and absolute numbers of CD14+CD16+ monocytes. A significant correlation was observed before the initiation of therapy between urinary neopterin and the relative numbers of CD3+CD4+ lymphocytes (rs = - 0.411, p < 0.01), absolute numbers of CD3+CD4+ lymphocytes (rs = - 0.313, p < 0.05), relative number of CD3+CD8+ lymphocytes (rs = 0.352, p < 0.05), CD4+/CD8+ ratio (rs = -0.404, p < 0.01), relative numbers of CD3+DR+ lymphocytes (rs = 0.343, p < 0.05), absolute numbers of CD3+DR+ lymphocytes (rs = 0.306, p < 0.05), and relative numbers of CD8+CD57+ lymphocytes (rs = 0.410, p < 0.01).

Urinary neopterin and peripheral blood leukocyte phenotype was followed in 44 breast carcinoma patients treated by primary chemotherapy with doxorubicin and paclitaxel before the start of the treatment and on 3 subsequent visits in approximately monthly intervals. Compared to pretreatment values, urinary neopterin, relative and absolute numbers of CD3+, CD3+CD4+ and CD8+CD28+ lymphocytes were significantly increased throughout the course of treatment. No significant changes were observed in relative and absolute numbers of NK cells, CD8+- CD57+, CD3+DR+, CD3+CD25+, and CD3+CD69+ lymphocytes. In contrast, the relative and absolute numbers of CD19+ lymphocytes and CD19+CD23+ lymphocytes were significantly decreased throughout the course of therapy. The relative and absolute numbers of monocytes were significantly increased throughout the course of therapy. Significantly increased absolute numbers were also observed for CD14+DR+ and CD14+CD16+ monocytes. Among 37 evaluable patients, pathological complete response of the primary tumor, including regional lymph nodes, was observed in 6 cases. In patients with pathological complete response relative and absolute numbers of lymphocytes and absolute numbers of CD4+ lymphocytes were significantly lower at baseline. A total of 18 patients had evidence of pathological involvement of the lymph nodes. Compared to patients with lymph node involvement detected in surgical specimen, 19 patients without lymph node involvement had at baseline significantly lower relative and absolute number of lymphocytes, absolute numbers of CD3+, CD3+CD4+, CD3+DR+ and CD8+CD57+ lymphocytes. When ratio of peripheral blood leukocyte counts at visit 2/visit 1 was calculated, patients without lymph node involvement at surgery also had significantly increased ratio of relative lymphocyte numbers, relative and absolute CD14+DR+ monocyte numbers.

In conclusion, systemic immune activation in breast carcinoma patients treated with doxorubicin and paclitaxel is associated with significant changes of peripheral blood leukocyte phenotype, including an increase of relative and absolute numbers of CD3+CD4+ lymphocytes.

Urinary Neopterin in Patients with Ovarian Cancer

Urinary neopterin, an indicator of systemic immune activation, is increased in most patients with epithelial ovarian carcinoma (EOC) and is an independent prognostic indicator. The data on prognostic significance of neopterin in EOC have been collected before the advent of paclitaxel that has changed the management and natural history of the disease. In the present study, we have evaluated the prognostic significance of urinary neopterin in 49 patients with primary and secondary ovarian neoplasms treated in the late 1990s and in 2000s. Urinary neopterin was measured by high-performance liquid chromatography. Compared to controls, urinary neopterin was significantly increased in patients with both primary ovarian cancer and ovarian metastases of other tumors (341 ± 343, and 328 ± 277 vs. 133 ± 40 μmol/mol creatinine; p <0.001 ). Serious toxicity of chemotherapy was observed in 8 out of 12 (67%) patients with urinary neopterin equal or above 338 μmol/mol creatinine (mean of all patients) compared to 2 of 19 ( 11%) of patients with urinary neopterin below 338 μmol/mol creatinine (Fisher exact test, p - 0.001). No significant changes were observed in urinary neopterin concentrations during the treatment with paclitaxel/platinum. A significant correlation was observed between urinary neopterin and percentage of xylose absorbed (rs = -0.58, p = 0.03), and positive correlations were observed between urinary neopterin and lactulose/ mannitol (rs = 0.63, p = 0.02), lactulose/xylose (rs = 0.79, p = 0.0007) and sucrose/xylose (rs = 0.60, p = 0.02) ratios. Survival was significantly longer in patients with urinary neopterin below 338 μιηοΐ/ιτιοί creatinine in the whole group of 49 patients with ovarian cancer, in 36 patients with primary ovarian cancer as well as in 13 patients in ovarian metastases of other primary tumors. A significant difference in survival was also observed when 37 pretreated patients or 24 pretreated EOC patients were evaluated (p = 0.05). In conclusion, neopterin remains a significant prognostic indicator in patients with recurrent ovarian cancer in the era of newer chemotherapeutic agents. Increased urinary neopterin was associated with chemotherapy toxicity.

Establishment, growth and in vivo differentiation of a new clonal human cell line, EM-G3, derived from breast cancer progenitors

A new clonal cell line, EM-G3, was derived from a primary lesion of human infiltrating ductal breast carcinoma. The line consisted of cuboidal cells with occasional appearance of more differentiated branched cells apparently involved in cell-to-cell communication. The EM-G3 cells, population doubling time 34 h, are dependent on the epidermal growth factor. Multicolor fluorescence in situ hybridization (mFISH) analysis demonstrated a stable diploid genome with several genetic changes. Immunocytochemical analysis of EM-G3 in vitro revealed positivity for keratins (K) K5, K14, K18, nuclear protein p63, epithelial membrane antigen (EMA) and other proteins indicative of a pattern of mammary epithelium bipotent progenitors. Detection of integrins alpha-6, beta-1, and protein CD44 by cDNA array also pointed to the character of basal/stem cells. In contrast, dominant cells in the human original tumor showed the luminal character (K18+, K19+, K5-, K14-, and p63-). However, cells with the immunocytochemical profile similar to that of cultured EM-G3 cells were found in minor clusters in the patient's tumor sections. The EM-G3 cells formed limited tumors in nu/nu mice. The cells in mouse tumors were organized in primitive ductal-like structures consisting of 1-3 large central luminal-like cells (EMA+) surrounded by peripheral myoepithelial-like cells (p63+/EMA-). The large central cells gradually disintegrated, forming a pseudolumen. Apparently, EM-G3 cells are able to partially differentiate in vivo as well as in vitro. Our results indicate that EM-G3 cells were derived from a premalignant population of common progenitors of luminal and myoepithelial cells that were immortalized in an early stage of tumorigenesis.

Survival after oxaliplatin therapy of irinotecan-pretreated advanced colorectal cancer patients

BACKGROUND/AIMS

The activity of oxaliplatin (OHP) and irinotecan (CPT) alone or in combination with 5-fluorouracil (5-FU) in advanced colorectal cancer is comparable, but there are limited data on the effectiveness of oxaliplatin in patients pretreated by irinotecan.

METHODOLOGY

We have analyzed retrospectively the survival of 77 consecutive advanced colorectal cancer patients treated with OHP after previous CPT therapy. Multivariate analysis was performed by Cox regression method, with the results expressed as hazard ratio (HR).

RESULTS

The median survival from the start of OHP therapy was 10.7 months (1-year survival 43%). The median survival was not reached in 10 patients treated by hepatic arterial infusion of OHP (>10.6 months). The median survival from the diagnosis of advanced/metastatic disease was 34.3 months. On multivariate analysis, hemoglobin <125g/L (HR=2.42), neutrophils <5200 per microL (HR=0.36), duration of advanced/metastatic disease <21 months (HR=2.40) and interval from last CPT administration <3 months (HR=0.27) were statistically significant (p<0.05) independent predictors of survival from the start of OHP treatment, but only hemoglobin (HR=2.07), neutrophils (HR=0.32) and CEA <100microg/L (HR=0.44) were independent predictors of survival from the last CPT. There were 4 treatment-induced deaths after combination of OHP and raltitrexed (TOMOX).

CONCLUSIONS

More than 40% of patients pretreated by irinotecan survived 1 year after start of OHP therapy. The therapy was similarly effective as a second or higher line of treatment. Hemoglobin levels and neutrophil count were independent factors associated with survival. The number of toxic deaths observed after TOMOX is alarming.

Phenotype of peripheral blood leukocytes and survival of patients with metastatic colorectal cancer

Immune dysfunction is prevalent in metastatic cancer. Few patients with colorectal cancer metastases are cured, and among the strategies aimed at improving the therapeutic results in patients with metastatic colorectal cancer, immunotherapy is being increasingly investigated. We evaluated retrospectively the prognostic significance of peripheral blood leukocytes in 59 patients with metastatic colorectal cancer. The relative numbers of CD3+, CD3+CD4+, CD3+CD8+, NK (CD3-CD16+CD56+), CD3+DR+, CD3+CD25+, CD3+CD69+, CD19+, CD19+CD23+, CD8+CD28+, CD8-CD28+, CD8+CD57+, CD14+DR+ and CD14+CD16+ leukocytes were analyzed by two-color flow cytometry. A three-step approach was adopted to identify predictors of prognosis using regression analysis. Based on the results of univariate survival analysis, the absolute number of white blood cells, NK/CD3+CD69+ and NK/white cell count ratios were significant indicators of prognosis. In the multivariate regression analysis a model was obtained using a single parameter, the NK/CD3+CD69+ ratio, predicting the survival with 10-15% power of regression. The present results indicate that the NK/CD3+CD69+ ratio in peripheral blood may be an independent variable in a regression model predicting the overall survival of patients with colorectal cancer metastases to be tested in prospective studies.

Origin of cells cultured in vitro from human breast carcinomas traced by cyclin D1 and HER2/neu FISH signal numbers

BACKGROUND

We have developed and optimized a feeder layer method for cultivation of normal human mammary luminal cells and found it suitable for establishing more than 150 primary cultures from individual human breast carcinomas. Here, we investigated if the malignant cells that are in situ additionally characterized by increased numbers of proto-oncogenes can be traced by the FISH method in the ex vivo-derived cultures.

MATERIALS AND METHODS

Paraffin sections from 9 tumors with derived cell cultures kept frozen in our cell bank were screened by FISH for cyclin D1 (CCND1) and c-erb-B2 (HER2/neu) proto-oncogene signal numbers.

RESULTS

In 6 tumors (5 primary tumors, 1 cutaneous metastasis), increased numbers of FISH signals were found in 55-99% of cells. Then, the relevant cell cultures were FISH screened; in cell populations maintained for up to 2-6 passages in vitro the incidence of cells with increased FISH signals was found to be low (2-16%). Moreover, the cells with multiplied signals that survived more than one passage in vitro were evidently unable to divide further. However, in all 6 tumors at least a small fraction of cells displaying only two signals of CCND1 or HER2/neu genes was identified directly in invasive tumor structures in the vicinity of cells with multiple signals.

CONCLUSION

Our findings suggest that these invasive tumor cells displaying only two proto-oncogene signals were most probably involved in the initiation and propagation of ex vivo tumor-derived primary cell cultures.

Calibration and quantification of fast intracellular motion (FIM) in living cells using correlation analysis

Video rate confocal laser scanning microscopy at the highest spatial and temporal resolution of backscattered light (BSL) imaging allowed for regular observation of fast intracellular motion (FIM) first revealed in living neoplastic cells. However, the absence of an objective evaluation has hampered further study of the mechanisms and biological significance of FIM. Particularly, a quantification of apparent differences in velocities that would complement and improve the current demonstration of FIM by color coding using the combination of red-green-blue (RGB) images had been missing. Standard methods of tracking or pattern recognition could not be applied because of the fuzzy nature of images of FIM. A search for a suitable method led to correlation analysis. It was calibrated on Brownian motion and a known type of motion, such as cell marginal ruffling, compared with FIM. Results approved its explanatory potential. Therefore, several crucial incidences of FIM could be analyzed. Apart from an argument against viewing FIM as a manifestation of simple Brownian motion, the correlation analysis of FIM in the adjacent peripheries of a rat fibroblast and a K4 rat sarcoma cell confirmed the notion of higher and uneven distribution of velocity of FIM in a tumor cell so far shown in color-coded images only. This result and other yet unpublished observations indicate that the velocity and topology of FIM can also contribute to a biological distinction between neoplastic and normal cells. Regular application of the correlation analysis should further expand the study of FIM for its mechanisms and predictive value. Such an approach should be thoroughly examined for a contribution to the knowledge of cancer cells.

Assessment of in vitro drug resistance of human breast cancer cells subcultured from biopsy specimens

The low cellular yield of a breast cancer sample represents a limiting factor for in vitro chemosensitivity/chemoresistance testing. The use of in vitro serially cultured cells can help overcome this obstacle.

MATERIALS AND METHODS

In vitro drug resistance of cells cultured from mammary carcinomas by the 3T3 feeder-layer technique was tested by the MTT assay. Out of the 33 tested cultures, 9 were derived from cells obtained from true-cut biopsies of primary tumours, with sample volume less than 0.03 cm3. The cultures were treated with 6 anticancer drugs at 6-8 concentrations. The chemoresistance of cultured cells was monitored by the surviving cell fraction as a function of the drug concentration.

RESULTS

The average time to obtain a result was 28 days. The volume of an original sample had no effect on the in vitro resistance of a culture, suggesting minimal alteration of in vitro chemosensitivity of cells by their cultivation. Histopathological grade, estrogen receptor status or expression of the c-erb-B2 protein of the original tumours did not significantly correlate with the resistance of cultures. Individual drugs displayed distinct in vitro effectiveness. Paclitaxel and cisplatin were the most potent drugs. Gemcitabine, vinorelbine and mafosfamide were the least potent drugs. Doxorubicin and gemcitabine most frequently failed to completely metabolically inhibit 100% of cultured cells at any concentration.

CONCLUSION

Combination of the optimised feeder-layer cultivation technique and the MTT test permits extensive drug resistance testing from very small breast cancer samples.

Effect of irinotecan on the phenotype of peripheral blood leukocyte populations in patients with metastatic colorectal cancer

BACKGROUND/AIMS

Previous studies have demonstrated a significant decrease in absolute numbers of CD3+CD4+, CD8+CD28+ and CD19+ lymphocytes, and an increase in the expression of activation markers on T-cells and the number of CD14+CD16+ monocytes in patients with metastatic cancer. Irinotecan (CPT-11) is now being widely used for treatment of metastatic colorectal cancer patients.

METHODOLOGY

We have examined, by two-color flow cytometry, peripheral blood leukocyte populations before and during systemic treatment with CPT-11 in 14 patients with metastatic colorectal cancer.

RESULTS

CD3+, CD3+CD4+, CD3+CD8+, CD8+CD28+ and CD19+ were significantly lower, and CD3+HLA-DR+ and CD14+CD16+ cells were higher in metastatic colorectal cancer patients compared to controls. After 2-4 months of CPT-11-based chemotherapy, significant increase in CD3+CD4+ cell numbers was observed in 8 patients who had initial CD3+CD4+ counts of less than 600 per microL (358 +/- 154 vs. 652 +/- 319 cells per microL, Wilcoxon test, P < 0.01), while in patients with higher initial CD3+CD4+ counts a trend for decrease was observed during therapy. A trend for an increase in CD8+CD28+ cell counts was observed in patients with low CD3+CD4+ numbers, but no other changes were observed during the treatment in other peripheral blood leukocyte populations examined.

CONCLUSIONS

CD3+CD4+ lymphocytopenia, a decrease in CD8+CD28+ and CD19+ lymphocytes, increased expression of activation markers and CD14+CD16+ monocytosis are present in a significant proportion of metastatic colorectal cancer patients. CPT-11-based therapy seems to ameliorate CD3+CD4+ lymphocytopenia, possibly by neutralizing the immunosuppressive effects of uncontrolled tumor growth. These observations may be useful for the design of immunotherapy trials in metastatic colorectal cancer.

Fast intracellular motion in the living cell by video rate reflection confocal laser scanning microscopy

Fast intracellular motion (FIM) was first revealed by back scattered light (BSL) imaging in video rate confocal scanning laser microscopy (VRCSLM), beyond the limits of spatial and temporal resolution obtainable with conventional optical microscopy. BSL imaging enabled visualisation of intra and extracellular motion with resolution in space down to 0.2 microm and in time to 1/25th of a second. Mapping the cell space at 0.2 microm x 0.2 microm (XY = in instantaneous best focal plane) x 0.5 microm (Z = height/depth, optic axis direction) volume steps revealed a communication layer above the known contact layer and an integrated dynamic spatial network (IDSN) towards the cell centre. FIM was originally observed as localised quasichaotic dancing (dithering) or reflecting patches/spots in the cell centre, faster in the darker nuclear space. Later, a second type of FIM was recognised which differed by the presence of a varied proportion of centrifugal and centripetal directional movements and/or jumping of patches/spots in the cell centre and outside the nuclear space. The first type is characteristic for cells in slightly adverse conditions while the second type has so far only been found in eutrophic cells. Temporal speeding up and coarsening of FIM, followed by slowing and eventually cessation at cell death, was found on exposure to strong stressors. It was concluded that the state of FIM provides instantaneous information about individual cell reactions to actual treatment and about cell survival. A putative switch between the first and second type FIM could be considered as an indicator of timing of cellular processes. The significance of FIM for the biology of the cell is seen in the rapid assessment of the condition of an individual live cell investigated by combination of various methods. Requirements for further development of this approach are outlined.

Video rate confocal laser scanning reflection microscopy in the investigation of normal and neoplastic living cell dynamics

The introduction of video rate confocal laser scanning microscopes (VRCLSM) used in reflection mode with high magnification, high aperture objective lenses and with further magnification by a zoom facility allowed the first detailed observations of the activity of living cytoplasm and offered a new tool for investigation of the structural transition from the living state to the specimen fixed for electron microscopy (EM). We used a Noran Odyssey VRCLSM in reflection (backscattered) mode. A greater degree of oversampling and more comfortable viewing of the liver or taped video image was achieved at zoom factor 5, giving a display monitor field width of 10 microns. A series of mesenchyme derived cell lines--from normal cells to sarcoma cells of different malignancy--was used to compare behaviour of the observed intracellular structures and results of fixation. We contrasted the dynamic behaviour of fine features in the cytoplasm of normal and neoplastic living cells and changes induced by various treatments. The tubulomembraneous 3D structure of cytoplasm in living cells is dynamic with motion observable at the new limits of resolution provided by VRCLSM. All organelles appear integrated into one functional compartment supporting the continuous 3D trafficking of small particles (vesicles). This integrated dynamic spatial network (IDSN) was found to be largest in neoplastic cells.

High temporal and spatial resolution studies of bone cells using real-time confocal reflection microscopy

Chick and rat bone-derived cells were mounted in sealed coverslip-covered chambers; individual osteoclasts (but also osteoblasts) were selected and studied at 37 degrees C using three different types of high-speed scanning confocal microscopes: (1) A Noran Tandem Scanning Microscope (TSM) was used with a low light level, cooled CCD camera for image transfer to a Noran TN8502 frame store-based image analysing computer to make time lapse movie sequences using 0.1 s exposure periods, thus losing some of the advantage of the high frame rate of the TSM. Rapid focus adjustment using computer controlled piezo drivers permitted two or more focus planes to be imaged sequentially: thus (with additional light-source shuttering) the reflection confocal image could be alternated with the phase contrast image at a different focus. Individual cells were followed for up to 5 days, suggesting no significant irradiation problem. (2) Exceptional temporal and spatial resolution is available in video rate laser confocal scanning microscopes (VRCSLMs). We used the Noran Odyssey unitary beam VRCSLM with an argon ion laser at 488 nm and acousto-optic deflection (AOD) on the line axis: this instrument is truly and adjustably confocal in the reflection mode. (3) We also used the Lasertec 1LM11 line scan instrument, with an He-Ne laser at 633 nm, and AOD for the frame scan. We discuss the technical problems and merits of the different approaches. The VRCSLMs documented rapid, real-time oscillatory motion: all the methods used show rapid net movement of organelles within bone cells. The interference reflection mode gives particularly strong contrasts in confocal instruments. Phase contrast and other interference methods used in the microscopy of living cells can be used simultaneously in the TSM.

Video-rate confocal reflection microscopy of neoplastic cells: rate of intracellular movement and peripheral motility characteristic of neoplastic cell line (RSK4) with high degree of growth independence in vitro

Video-rate laser confocal interference reflection microscopy was used to demonstrate rapid motion of intracellular organelles and features at the cell periphery in a fully transformed neoplastic cell line, RSK4, and in four other neoplastic cell populations. In the RSK4 cells, vibrational and trafficking movements of intracellular particles at a rate greater than 25 Hz and ranging down to 5 Hz were recorded. Rapidly moving processes changed to ruffles, then microspikes, and previously undetectable ephemeral intercellular contacts were seen. Dynamic cyclical changes were revealed in the sizes of the podosomal close contacts of the transformed cells. The visibility of such features and the temporal and spatial resolution are improved over earlier methods. The fact that fast cellular and intracellular movements can be detected with this microscopic technique offers new possibilities in attempting to recognise differences between unimpaired living cells, and it may prove useful in the identification of malignant cells.

Behaviour of osteoclasts in vitro: contact behaviour of osteoclasts with osteoblast-like cells and networking of osteoclasts for 3D orientation

The cell-cell contact-induced behaviour of osteoclasts and osteoblasts in vitro was investigated by time-lapse videomicroscopy. Contact interactions of osteoclasts with autologous cells, derived mostly from chick but also from rat bones, included contact inhibition, failure of contact inhibition, contact guidance along stabilised edges of other cells, and underlapping of other cells. Message-mediated contact behaviour (MMCB) between osteoclasts and autologous osteoblastic cells resulted, after a time delay, in zeiosis of the osteoblast-like cell which could continue, or even begin, after the osteoclast broke contact, leading to retraction of the cell and occupation of its position by the osteoclast. MMCB may play a part in the breaching of the osteoblastic sheet by osteoclasts and, in general, in the malignant spread of neoplastic cells. Two or more osteoclasts were often joined by connecting and coordinating tubules (CCTs) of varied, and varying, lengths and widths. Osteoclasts could travel along the CCTs in both directions, or send nuclei through them. The CCTs became temporarily attached to the surface of other cells, or to the substrate, then acting as a temporary anchorage for orientation and for the return of the cell to the same spot. The dynamics of osteoclastic behaviour suggest that such a networking of osteoclasts is valuable for the 3D coordination of their role in bone turnover.

Microscopy of bone cells, bone tissue, and bone healing around implants

Newer methods of scanning microscopy using both light and electrons are particularly relevant to the study of bone cells, bone matrix organization, matrix mineralization, bone modeling and remodeling, and the adaptation of cells and matrix to implants. Most of such studies are conducted on retrieved implants, at least after the death of the related tissue. Because the retention of the tissue-implant relationship in such preserved tissue is crucial for critical evaluation of the implant, methods based on the study of flat surfaces of embedded tissue blocks are very important. Using electrons, the backscattered electrons in a scanning electron microscope can be employed to evaluate mean atomic number (density) and cathodoluminescence can identify polymers and fluorescent labels. Using light, confocal microscopical techniques permit the examination of layers deep to the block face. Confocal reflected and fluorescence methods allow the study of cell behavior upon both transparent and opaque substrates in the laboratory. Examples of the above are presented and interpretation problems discussed. Current experiments are aimed at enabling the study of bone wound healing and bone adaptation to implanted materials in vivo, through the implantation of optical quality windows and/or newly conceived and designed microscopical objective lenses.