Understanding host-graft crosstalk for predicting the outcome of stem cell transplantation

Mesenchymal stromal cells (MSCs) hold great promise for tissue regeneration in debilitating disorders. Despite reported improvements, the short-term outcomes of MSC transplantation, which is possibly linked to poor cell survival, demand extensive investigation. Disease-associated stress microenvironments further complicate outcomes. This debate underscores the need for a deeper understanding of the phenotypes of transplanted MSCs and their environment-induced fluctuations. Additionally, questions arise about how to predict, track, and comprehend cell fate post-transplantation. In vivo cellular imaging has emerged as a critical requirement for both short- and long-term safety and efficacy studies. However, translating preclinical imaging methods to clinical settings remains challenging. The fate and function of transplanted cells within the host environment present intricate challenges, including MSC engraftment, variability, and inconsistencies between preclinical and clinical data. The study explored the impact of high glucose concentrations on MSC survival in diabetic environments, emphasizing mitochondrial factors. Preserving these factors may enhance MSC survival, suggesting potential strategies involving genetic modification, biomaterials, and nanoparticles. Understanding stressors in diabetic patients is crucial for predicting the effects of MSC-based therapies. These multifaceted challenges call for a holistic approach involving the incorporation of large-scale data, computational disease modeling, and possibly artificial intelligence to enable deterministic insights.

Mesenchymal Stem Cell-Derived Exosomes Modulate Angiogenesis in Gastric Cancer

Individualized gastric cancer (GC) treatment aims at providing targeted therapies that translate the latest research into improved management strategies. Extracellular vesicle microRNAs have been proposed as biomarkers for GC prognosis. Helicobacter pylori infection influences the therapeutic response to and the drivers of malignant changes in chronic gastritis. The successful use of transplanted mesenchymal stem cells (MSCs) for gastric ulcer healing has raised interest in studying their effects on tumor neovascularization and in potential antiangiogenic therapies that could use mesenchymal stem cell secretion into extracellular vesicles—such as exosomes—in GC cells. The use of MSCs isolated from bone marrow in order to achieve angiogenic modulation in the tumor microenvironment could exploit the inherent migration of MSCs into GC tissues. Bone marrow-derived MSCs naturally present in the stomach have been reported to carry a malignancy risk, but their effect in GC is still being researched. The pro- and antiangiogenic effects of MSCs derived from various sources complement their role in immune regulation and tissue regeneration and provide further understanding into the heterogeneous biology of GC, the aberrant morphology of tumor vasculature and the mechanisms of resistance to antiangiogenic drugs.

The mesocolic apical fragment in complete mesocolic excision colectomies: Should it be analysed separately? A proof-of-concept study

AIM

The aim of this work is to describe a protocol and assess the feasibility of harvesting and analysing the mesocolic apical fragment (MAF) for the presence of central lymph node (LN) metastasis and extra lymphatic free tumour cells in a random subgroup extracted from a cohort of complete mesocolic excision colectomies with central vascular ligation.

METHOD

Forty-seven patients diagnosed with colorectal cancer were included. A 2/2 cm pyramid of tissue was cut around the central tie and sent for pathological examination. The MAF was sectioned into 16 slices. High-definition images were taken from the slices which were merged into a panoramic three-dimensional image of the MAF. The distribution of LNs in the MAF was quantified. Immunohistochemistry staining for cytokeratin 14 was used to identify isolated tumour cells and micrometastases in the extranodal tissue.

RESULTS

No tumoural cells migrating through the apical zone, outside of the LNs, were identified. Margins of resection, mesocolic tissue and LNs were all negative in the subgroup of ultrastaged MAFs. The number of examined central LNs varied between 0 and 24, with positive MAF LNs being identified only in pN2 stages. The rate of positive apical LNs in our cohort was 4.2% (n = 2).

CONCLUSIONS

The MAF can be easily extracted from standard specimens, allowing for accurate analysis of lymphatic and extra-nodal tumour cells on the central resection margins, in central LNs and in the apical mesocolic tissue. Future research on larger cohorts is required to establish if analysing the MAF has an impact on patient staging, prognosis and management.

NHF-derived carbon dots: prevalidation approach in breast cancer treatment

Metastatic breast cancer dominates the female cancer-related mortality. Tumour-associated molecules represents a crucial for early disease detection and identification of novel therapeutic targets. Nanomaterial technologies provide promising novel approaches to disease diagnostics and therapeutics. In the present study we extend the investigations of antitumoral properties of Carbon Dots prepared from N-hydroxyphthalimide (CD-NHF) precursor. We evaluate the effect of CD-NHF on tumour cell migration and invasion in vitro and their impact on tumour progression using an in vivo model. Furthermore, we investigate the molecular mechanisms involved in CD-NHF antitumour effects. In vivo mammary tumours were induced in Balb/c female mice by injecting 4T1 cells into the mammary fat pad. Conditional treatment with CD-NHF significantly impair both migration and invasion of metastatic breast cancer cells. The presence of CD-NHF within the 3D cell cultures strongly inhibited the malignant phenotype of MDA-MB-231, 4T1 and MCF-7 cells in 3D culture, resulting in culture colonies lacking invasive projections and reduction of mammospheres formation. Importantly, breast tumour growth and metastasis dissemination was significantly reduced upon CD-NHF treatments in a syngeneic mouse model and is associated with down-regulation of Ki67 and HSP90 expression. CD-NHF nanostructures provide exciting perspective for improving treatment outcome in breast cancer.

Long-Term Deleterious Effects of Short-term Hyperoxia on Cancer Progression-Is Brain-Derived Neurotrophic Factor an Important Mediator? An Experimental Study

Perioperative factors promoting cancer recurrence and metastasis are under scrutiny. While oxygen toxicity is documented in several acute circumstances, its implication in tumor evolution is poorly understood. We investigated hyperoxia long-term effects on cancer progression and some underlying mechanisms using both in vitro and in vivo models of triple negative breast cancer (TNBC). We hypothesized that high oxygen exposure, even of short duration, may have long-term effects on cancer growth. Considering that hyperoxic exposure results in reactive oxygen species (ROS) formation, increased oxidative stress and increased Brain-Derived Neurotrophic Factor (BDNF) expression, BDNF may mediate hyperoxia effects offering cancer cells a survival advantage by increased angiogenesis and epithelial mesenchymal transition (EMT). Human breast epithelial MCF10A, human MDA-MB-231 and murine 4T1 TNBC were investigated in 2D in vitro system. Cells were exposed to normoxia or hyperoxia (40%, 60%, 80% O₂) for 6 h. We evaluated ROS levels, cell viability and the expression of BDNF, HIF-1α, VEGF-R2, Vimentin and E-Cadherin by immunofluorescence. The in vivo model consisted of 4T1 inoculation in Balb/c mice and tumor resection 2 weeks after and 6 h exposure to normoxia or hyperoxia (40%, 80% O₂). We measured lung metastases and the same molecular markers, immediately and 4 weeks after surgery. The in vitro study showed that short-term hyperoxia exposure (80% O₂) of TNBC cells increases ROS, increases BDNF expression and that promotes EMT and angiogenesis. The in vivo data indicates that perioperative hyperoxia enhances metastatic disease and this effect could be BDNF mediated.

Association of intracellular lipid accumulation in subcutaneous adipocyte precursors and plasma adipokines in bariatric surgery candidates

BACKGROUND

The adipocyte expansion is a critical process with implications in the pathogenesis of obesity associated metabolic syndrome. Impaired adipogenesis leads to dysfunctional, hypertrophic adipocytes, local inflammation and peripheric insulin resistance.

METHODS

We assessed the relationship between the adipogenic differentiation capacity of the subcutaneous adipose derived stem cells (ASCs), evaluated by total lipid accumulation, and the metabolic and hormonal profile in a group of obese female patients proposed for bariatric surgery (N = 20) versus normal weight female controls (N = 7).

RESULTS

The lipid accumulation (measured as optical density at 492 nm) of ASCs during their differentiation to adipocytes was significantly lower in ASCs isolated from obese patients as compared to ASCs isolated from normal weight patients (0.49 ± 0.1 vs. 0.71 ± 0.1, p < 0.001). Significant negative correlations between lipid accumulation in adipogenic differentiated ASCs and plasma concentrations of triglycerides (p < 0.01), insulin (p < 0.001), HOMA-IR (p < 0.01), adiponectin (p < 0.05) and leptin/adiponectin ratio (p < 0.05) were found in obese group.

CONCLUSIONS

In severely obese female patients, the abnormal adipogenesis is related to insulin resistance and leptin/adiponectin ratio. The abnormal lipid accumulation in the mature adipocyte derived from obese ASCs could possible predict the further development of type 2 diabetes mellitus in severely obese patients and influence the selection of patients for bariatric surgery.

The Unexplored Role of Intra-articular Adipose Tissue in the Homeostasis and Pathology of Articular Joints

Intra-articular adipose tissue deposits known as articular fat pads (AFPs) are described to exist within synovial joints. Their assumed role in normal joint biomechanics is increasingly objectivized by means of advanced methods of functional imaging. AFPs possess structural similarity with body subcutaneous white adipose tissue (WAT), however, seems to be regulated by independent metabolic loops. AFP dimension are conserved during extreme WAT states: obesity, metabolic syndrome, lipodystrophy, and cachexia. Hoffa fat pad (HFP) in the knee is increasingly recognized as a major player in pathological joint states such as anterior knee pain and osteoarthritis. HFP contains numerous population of mesenchymal and endothelial progenitors; however, the possible role of mature adipocytes in the maintenance of stem cell niche is unknown. We propose that AFP is an active component of the joint organ with multifunctional roles in the maintenance of joint homeostasis. Endowed with a rich network of sensitive nervous fibbers, AFPs may act as a proprioceptive organ. Adipokines and growth factors released by AFP-resident mature adipocytes could participate in the maintenance of progenitor stem cell niche as well as in local immune regulation. AFP metabolism may be locally controlled, correlated with but independent of WAT homeostasis. The identification of AFP role in normal joint turnover and its possible implication in pathological states could deliver diagnostic and therapeutic targets. Drug and/or cell therapies that restore AFP structure and function could become the next step in the design of disease modifying therapies for disabling joint conditions such as osteoarthritis and inflammatory arthritis.

MIDDLE TERM IMPACT OF SLEEVE GASTRECTOMY ON MAJOR CARDIOVASCULAR RISK FACTORS IN A GROUP OF ROMANIAN OBESE PATIENTS

BACKGROUND AND AIM

The goals of bariatric surgery are to improve the quality of life by lowering body mass index (BMI) but also to treat obesity comorbidities. The aim of our study was to evaluate the impact of laparoscopic sleeve gastrectomy (LSG) on metabolic parameters.

METHODS

85 obese patients treated by bariatric surgery LSG procedure were included in the study. Basal, 6 and 12 months after surgery serum glucose levels and lipid fractions were measured. Metabolic syndrome criteria according to IDF 2006 were evaluated at baseline and after bariatric surgery.

RESULTS

Our group included 61.2 % female patients, the mean age was 40.2 ±10.2 years and the metabolic syndrome criteria at baseline were confirmed in 69.4% of the study group. At twelve months after the intervention, the mean excess weight loss (%EWL) was 72%, with age and BMI subgroups variations. We found significant improvements of serum concentrations for triglycerides (P-value = 0.001, decreased by 30%), HDL-cholesterol (P-value = 0.017, increased by 26%), total cholesterol (P-value = 0.043, decreased by 12%) and glucose (P-value = 0.007, decreased by 12%).

CONCLUSIONS

The positive effect of bariatric surgery was confirmed for lipid fractions and fasting glucose levels, also the metabolic syndrome prevalence was significantly reduced, all these changes contribute to lower cardiovascular risk together with significant weight loss.

VITAMIN D AND TISSULAR EXPRESSION OF VITAMIN D RECEPTOR IN OBESITY

Vitamin D (VitD), a lipid-soluble hormone, is able to regulate the transcription of many genes through vitamin D receptor (vitD receptor-VDR). It has been shown that VitD deficiency is associated with obesity, characterized by a low degree inflammatory state, which contribute to the pathogeny of metabolic syndrome and type 2 diabetes mellitus. VitD deficiency is a public health problem, at the same time the global prevalence of obesity and cardiovascular diseases is continuously growing. Evidence from recent studies on animal models suggest that VitD or VDR deficiency promotes cardiomyocyte hypertrophy, which can be one of the mechanisms for increasing cardiovascular risk. The heart is one of the target organs of action for VitD, because VDR is expressed in cardiomyocytes. Also, previous in vitro studies have shown that VitD is able to inhibit the production of monocyte chemotactic factors (MCP-1) and other pro-inflammatory mediators in human preadipocytes and mature adipocytes. Inflammation is an important factor in the pathogenesis of atherosclerosis. In obesity there are not known data about correlations between plasma levels of VitD and VDR expression in the subcutaneous fat tissue, epicardial visceral adipose tissue, and in particular in myocardium. Also, there are still no studies to test VDR expression in myocardial cells and to investigate the results of dietary VitD supplementation on the expression of VDR in the epicardial adipose tissue and myocardium.

CONCENTRATIONS OF VITREAL CYTOKINES IN RHEGMATOGENOUS RETINAL DETACHMENT

Proliferative vitreoretinopathy (PVR) is one of the most frequent causes of failure of rhegmatogenous retinal detachment (RRD) surgery.

AIM

To measure the vitreous levels of granulocyte colony stimulating factor (G-CSF) and monocyte chemoattractant protein 1 (MCP-1) in eyes with RRD and in a control group.

MATERIAL AND METHODS

A prospective study of 40 patients operated for RRD (study group) and 20 patients with epiretinal membrane or macular holes (selected as control group since they needed vitrectomy but had attached retinas). Vitreous samples were collected during vitrectomy and were assessed for the presence of cytokines using a fluorescent bead-based multiplex assay.

RESULTS

The concentration of G-CSF (8.59 pg/ml) and MCP-1 (1615.2 pg/ml) were significantly increased in the study group, when compared to the control group (0 and 469.13 pg/ml, respectively). MCP-1 was also significantly increased in the subgroup of patients with PVR compared to the patients with uncomplicated RRD.

CONCLUSIONS

The levels of these biomarkers support the idea that proliferative vitreoretinopathy has an inflammatory component.

Clinical and histological predictive risk factors of atrial fibrillation in patients undergoing open-heart surgery

Postoperative atrial fibrillation (POAF) is a common complication subsequent to cardiac surgery. Various risk factors have been reported for the development of this complication; however, their precise role in POAF is unknown. In the present study, we attempted to identify clinical factors and histopathological changes in atrial tissue that may predict the development of POAF. Atrial tissue was sampled from 103 patients in sinus rhythm that had undergone open-heart surgery, including elective coronary artery bypass grafting (79.61%) and heart valve surgery (20.38%). Atrial surgical biopsies were obtained from the right atrial appendage at the site of cannulation, prior to cardiopulmonary bypass. Tissues were processed routinely for light microscopy, then stained with hematoxylin and eosin and sirius red. Microscopical exams were used to observe the atrial lesions and morphometry was conducted for quantification. In total, 37 patients (35.92%) developed POAF and atrial lesions were identified in the majority of patients in the normal postoperative sinus rhythm and POAF groups, but were most common in the POAF patients. The most common risk factors involved in developing POAF were found to be: Age of >60 years, male gender, ejection fraction of <50% and increased pulmonary hypertension. Furthermore, interstitial fibrosis and myocytolysis were the most common injuries identified. Abnormalities in atrial surgical biopsies may indicate the susceptibility of a patient to developing POAF. The present results suggest that the pre-existent alterations in the structure of the right atrium may be a major determinant in the development of POAF.

Stem cells for the treatment of musculoskeletal pain

Musculoskeletal-related pain is one of the most disabling health conditions affecting more than one third of the adult population worldwide. Pain from various mechanisms and origins is currently underdiagnosed and undertreated. The complexity of molecular mechanisms correlating pain and the progression of musculoskeletal diseases is not yet fully understood. Molecular biomarkers for objective evaluation and treatment follow-up are needed as a step towards targeted treatment of pain as a symptom or as a disease. Stem cell therapy is already under investigation for the treatment of different types of musculoskeletal-related pain. Mesenchymal stem cell-based therapies are already being tested in various clinical trials that use musculoskeletal system-related pain as the primary or secondary endpoint. Genetically engineered stem cells, as well as induced pluripotent stem cells, offer promising novel perspectives for pain treatment. It is possible that a more focused approach and reassessment of therapeutic goals will contribute to the overall efficacy, as well as to the clinical acceptance of regenerative medicine therapies. This article briefly describes the principal types of musculoskeletal-related pain and reviews the stem cell-based therapies that have been specifically designed for its treatment.

Potential value of in situ cellular immune response in HPV subtype 16 and 18 positive cervical cancer

There is no doubt that the association between infection of the cervical epithelium by carcinogenic Human Papilloma Virus (HPV), particularly types 16 and 18, and cervical cancer (CC) is responsible for the activation of the immune response (IR). Research on tumor infiltrating lymphocytes at the primary tumor site could give us important information on how the immune cells are fighting against cancer.

AIM

The aims of our study were to assess HPV status and to evaluate the significance of in situ cellular IR in CC.

MATERIALS AND METHODS

We performed a two-step retrospective analysis of IR in 18 CC: evaluation of HPV 16 and 18 infections by in situ hybridization and immune biomarkers (CD20, CD3, CD45) by immunohistochemistry. Immune cell profile, densities (assigned scores "0" if no inflammatory infiltrate, "1+" low, "2+" intense), tissue distribution and classical negative prognosis factors in relationship with survival and relapse were further assessed.

RESULTS

We successfully demonstrated HPV 16 and/or 18 in all cases. We reported statistical significant correlations (p<0.005) between CD3, CD20, CD45 and survival (r=0.800), relapse (r=-0.892), clinical stage (r=-0.914), tumor size (r=-1) as well as the association between survival and CC subtype (r=0.548), FIGO stage (r=-0.914), tumor size (r=-0.800) and grading (r=0.61).

CONCLUSIONS

The density of different immune cells is significantly involved in guiding prognosis of the CC in high-risk 16 and 18 HPV positive women; low cellular densities for CD3, CD20 and CD45 meaning limited immune response reflect negative disease outcomes promoting local relapse and decreased survival in such settings.

Current status in vitamin D and regulatory T cells--immunological implications

There has been a continuous effort to understand possible non-Ca metabolism roles of vitamin D, including its role in the immune system and, in particular, in T cell-medicated immunity. Vitamin D receptor is found in significant concentrations in the T lymphocyte and macrophage populations, when we refer to immune system, and pretty much in any human tissue and cells. Until the eighties, no one had imagined that vitamin D might play a role in the functioning of the immune system. Today we accepted that the normal immune system harbors a regulatory T cell (Treg) population specialized for immune suppression. Currently, the most commonly known regulatory T-cell lineage is called CD4+ CD25high FoxP3+ regulatory T cells. Several autoimmune disorders have been linked to a deficiency in vitamin D3. In some autoimmune diseases, including multiple sclerosis (MS), a compromised Treg function is believed to be critically involved in the disease process. Vitamin D insufficiency has ramifications not only for bone health, but also in other non-skeletal areas of vitamin D function, such as immune cells, muscle cells and, perhaps, adipocytes. As a final conclusion, further researches in the field of vitamin D, Tregs, immunity (inflammatory processes, rejection, autoimmune diseases, etc.), either in vitro on cell cultures or in vivo using lab animals or volunteers are still necessary.

Novel approaches for treating musculoskeletal diseases: molecular orthopedics and systems medicine

Molecular medicine uses knowledge about cell structure and function for disease, diagnostics, stage characterisation and treatment. The advent of genomic technologies is considerably leading to developments in the field of molecular medicine. The accumulation of detailed information about gene expression, epigenetic variability, protein transcription and functional modulation is contributing to a new era in medicine. Rapid and early diagnostic procedures, molecular characterisation of degenerative and proliferative diseases and personalized therapies are predicted to lead to advancements in health prevention and treatment of disease. Diagnostic tools and therapies based on local and /or general modulation of cellular processes for traumatic or degenerative musculoskeletal conditions are becoming available. A logical consequence of the information derived from extensive data gathering, systems biology and systemic medicine has lead to significant improvements in understanding biological structure and function in a simultaneous bottom top and integrative, holistic manner. The description of disease mechanism at an intimate, subcellular level has a dual benefit. A thorough understanding of the crosstalk involved in molecular pathways both in the normal and the diseased state are expanding scientific knowledge and simultaneously are enabling design cell-targeted and individualized therapies. This paper presents a brief overview of current molecular based treatments available to the orthopedic surgeon and introduces the concept of systemic medicine from the perspective of musculoskeletal pathology.

Isolation and phenotypic characterisation of stem cells from late stage osteoarthritic mesenchymal tissues

INTRODUCTION

Osteoarthritis (OA) represents an increasing health issue worldwide. Regenerative medicine (RM) has raised the hope for introducing revolutionary therapies in clinical practice. Detection of autologus cell sources can improve accessibility to RM strategies.

OBJECTIVES

To assess the presence and biological potential of mesehchymal stem cells in three tissues (subchondral bone, synovial layer, periarticular adipose tissue) in late stages osteoarthritic patients.

MATERIAL AND METHODS

Samples were collected from subjects undergoing total knee replacement (TKR). MSCs were isolated and cultured in complete αMEM with β FGF. Cell morphology and growth potential was assessed. Flow cytometry was used for detection of several relevant cell surface markers. Quantitative and qualitative assessment of differentiation potential towards three mesenchymal lineages (osteogenesis adipogenesis chondrogenesis) was performed. Time lapse life cell imaging of nondiferentiated cells over 24 hours period was used to determine cell kinetics.

RESULTS

Mesenchymal cells derived from all donors and tissue types showed morphology, growth and surface cell markers associated with stemness. All cell types underwent differentiation toward three mesenchymal lineages with significant differences between tissues of origin, not between donors. Cell kinetics, as derived from life imaging records, was variable with tissue of origin, significant higher for adipose derived MSCS.

CONCLUSION

Human late stage OA mesenchymal tissues, contain progenitors with proliferative and differentiation potential of MSCs. These populations can be used for research and autologus regenerative therapies. Further comparative studies with age matched non OA samples has the potential of contributing to deepening knowledge about disease occurrence and progression.

Abstract 2470: Adhesion-mediated dysfunctions in myelodysplastic syndromes microenvironment

Objectives: The recent evidences demonstrate that in myelodysplastic syndromes (MDS) a particular role is played by stromal microenvironment dysfunctions, which mediate the direct contact with hematopoietic precursor cells (HPC). The aims of our study were to assess the putative growth deficiencies of mesenchymal stromal cells (MSC) selected from MDS individuals, with regard to their ability to generate a microenvironment suitable to HPC development. Then, we intended to decode the focal adhesion (FA) signalling pathways and to understand whether adhesion-mediated processes contribute to transduction of intrinsic proliferative signals, as well as their impact on HPC-to-MSC interactions. Methods: To this end, we imagined a selection procedure using MSC specific markers expression (STRO-1 and CD73), we performed their phenotypic evaluation, and we conducted the functional assays on MSC and HPC selected from MDS patients vs. healthy volunteers. Finally, we have used the immunofluorescence microscopy to characterize the FA proteins (paxillin and focal adhesion kinase [FAK]), and of their regulators, p130CAS and HSP90. Results: The MSC production in STRO-1+ and CD73+ cell cultures from refractory cytopenia (RC) marrows was deficient, and, in addition, the clonogenic ability of these fractions was strongly diminished. The relative proliferation in MSC cultures from RC is the result of a continuous division process occurring at a low rate and lacking the ability to generate the normal functional progenitors required to form colonies. By contrast, in refractory anemia with excess of blasts (RAEB) settings, the proliferation rate is moderately improved due to the reduced doubling time of STRO-1 cells. However, this was not accompanied, at the end point, by complete functional maturity as reflected in the CFU-F number. Likewise, we have to point out the diminution of CFU-F capacity of CD73+ fractions in MDS that directly correlates with the CD44 mitigate on their surface. In addition, the doubling time of MSC from MDS inversely correlate with their expression for CD49e (Δ5-integrin). The proliferation differences occur in MDS cultures compared to normal settings can be attributed equally to the qualitative defects of FA proteins (FAK, and paxillin). The MSC from RAEB cultures highlight a strong complexation of FA proteins to HSP90 in nuclear area, which support a proliferative behaviour of these cells. Moreover, this high colocalisation to HSP90 indicates the cessation of proteasome-mediated recycling of these proteins. Furthermore, the preliminary results indicate the fact that the clonogenic potential of HPC is controlled by adhesion mechanisms dependent on stroma, and FAK is one of the molecules involved in this process. Conclusions: These data prove that MSC selected from MDS patients are intrinsically pathological and they could influence HSC behaviour by their direct interactions via FA proteins signalling.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2470. doi:1538-7445.AM2012-2470

Laser microdissection--a novel approach for accessing the molecular basis of cancer

BACKGROUND AND AIM

It has been known for quite a lot of time that tumours are cellular aggregates of different cells, mainly malignant cells but also immune cells--of which the most well-known are the tumour infiltrating lymphocytes (TIL) and the tumour associated macrophages (TAM). By observing hematoxylin--eosin stained or immunohistochemical stained slides belonging to different areas of the tumour it is clear that there are clusters of malignant cells within the tumour itself that seem to behave differently from the rest of the tumour. Another fact is that different areas of the tumour contain different inflammatory cells which may promote carcinogenesis or may help to confine it. Whereas different immune cells can be recognised by using immunohistochemistry, a satisfactory characterization of the molecular characteristics of the malignant clusters of the tumour cannot be made without further use of different molecular techniques such as different PCR techniques or microarray methods. Laser microdissection thus comes as a valuable aid in choosing exactly which cells will be analyzed further on.

PRINCIPLE OF THE METHOD

Laser microdissection is based on using the energy of a focused laser beam to cut through the thickness of the tissue that is placed on a microscope slide in order to obtain cell samples previously selected by the pathologist through special software.

CONCLUSIONS

To be able to cut the cells that you want and analyze them further without having them contaminated with other cells means that you can get more insight into the progression of the mutations that occur in these malignant cells, mutations that cause them to become more aggressive or multidrug-resistant. This could in time lead to the discovery of new molecular targets for cancer therapy.

Predictive value of cellular immune response in cervical cancer

Despite recent advances in the immune mechanisms of cervical cancer (CC), the relapse still remains an actual issue and recognition of new predictive biomarkers is essential.

AIM

The purpose of this retrospective study was to investigate possible differences in the primary, in situ, cellular immune response between cervical carcinoma with and without relapse.

MATERIAL AND METHODS

Paraffin-embedded tissue samples from 61 consecutive women with CC (34 with and 27 without relapse) were immunostained for CD3, CD20 and CD45 cells. Immune cell profile densities were further assessed, assigning scores between 0 and 3: "0" meaning the absence of inflammatory infiltrate, "1+" low, "2+" intense and "3+" intense infiltrate with lymphoid follicles. Statistical analysis was performed in SPSS-13 software, p<0.05.

RESULTS

Statistically significant intra- and peri-tumoral low numbers of several immune cell subtypes are strongly associated with relapse of disease within three and five years in patients with CC (p<0.05); moreover, statistical significant correlations between immune cells and both free survival (CD3: r=0.382; CD20: r=0.404; CD45: r=0.376) and relapse (CD3: r=-0.408; CD20: r=-0.355; CD45: r=-0.354) have been demonstrated. Only CD3 was reported as predictive biomarker of relapse in CC (ANOVA, t-Student, p<0.05).

CONCLUSIONS

Major differences in the cellular immune response among patients with cervical cancer with and without relapse within three and five years have been demonstrated. CD3 may be used as potential prognostic biomarkers, whereas the results are promising for adjuvant immunotherapy.

[Vascular molecular markers for determination of disease free survival (DFS) of breast cancer]

The heterogeneity of the evolution of breast cancer complicates patient management. The use of vascular markers as prognostic factors is a new and promising tool in medical oncology. Research data of the current decade demonstrate that angiogenesis plays substantial role in growth and spread of malignant tumor. At present, immunohistochemical determination of intratumoral microvascular density represents one of the more promising new prognostic indicators in breast cancer that needs to be further investigated to identify and standardize the method of choice to be tested in prospective clinical studies. Consequently markers of angiogenic activity have receiving increasing attention. By analyzing the evolution of 209 cases of breast cancer enrolled in a prospective study reaching the 5th year of follow up, we provide herein data supporting that Factor VIII and CD34 could be reliable markers for prognosis of DFS. Tumors with lower expression of Factor VIII and CD34 have a better prognostic and lower potential metastatic. The Factor VIII comparative with CD34 represents a more faithful prognostic marker. Angiogenesis markers have also become a putative therapeutic target.

Use of the presence of anti-protein gag antibodies as an evolution marker of HIV infection

The paper studies the modifications occurring in the prevalence of anti-protein gag antibodies during the evolution of the infection in a paediatric population iatrogenically infected and not submitted to antiretroviral treatment. The study was performed by annual clinical examination of children and by laboratory determinations: western-blot, p24 Ag assay, determination of lymphocyte population by flowcytometry. The predictive capacity of p17 antibodies was revealed, their occurrence after seroconversion pointing to a favourable evolution, with a longer asymptomatic period; the disappearance of these antibodies during the disease indicates a more advanced stage of the disease. The disappearance of p24 and p55 antibodies during the evolution of the disease shows a more advanced stage of the disease, both clinically and as concerning the immunosuppression degree.