Leszek Kraj

Dr. Leszek Kraj


Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 December 2020 in Cells
Verified
Journal Article
Open access
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LSLukasz Szymanski
Lukasz Szymanski
RSRafał Skopek
Rafał Skopek
MPMałgorzata Palusińska
Małgorzata Palusińska
TSTino Schenk
Tino Schenk
SSSven Stengel
Sven Stengel
SLSławomir Lewicki
Sławomir Lewicki
The retinoids are a group of compounds including vitamin A and its active metabolite all-trans-retinoic acid (ATRA). Retinoids regulate a variety of physiological functions in multiple organ systems, are essential for normal immune competence, and are involved in the regulation of cell growth and differentiation. Vitamin A derivatives have held promise in cancer treatment and ATRA is used in differentiation therapy of acute promyelocytic leukemia (APL). ATRA and other retinoids have also been successfully applied in a variety of dermatological conditions such as skin cancer, psoriasis, acne, and ichthyosis. Moreover, modulation of retinoic acid receptors and retinoid X (or rexinoid) receptors function may affect dermal cells. The studies using complex genetic models with various combinations of retinoic acid receptors (RARs) and retinoid X (or rexinoid) receptors (RXRs) indicate that retinoic acid and its derivatives have therapeutic potential for a variety of serious dermatological disorders including some malignant conditions. Here, we provide a synopsis of the main advances in understanding the role of ATRA and its receptors in dermatology.

11 October 2017 in Nutrients
Verified
Journal Article
Open access
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MZMonika Aleksandra Ziętarska
Monika Aleksandra Ziętarska
JKJoanna Krawczyk-Lipiec
Joanna Krawczyk-Lipiec
LKLeszek Kraj
Leszek Kraj
RZRenata Zaucha
Renata Zaucha
SMSylwia Malgorzewicz
Sylwia Malgorzewicz
Background: Cancer disease is usually associated with impaired nutritional status, which is one of the factors contributing to deterioration of the results of surgery, chemotherapy or radiotherapy. Objectives: The aim of the study was to determine whether nutritional support with high protein (ONS) in adult oncologic patients in the first step of cancer cachexia—asymptomatic precachexia, has an influence on the toxicity of systemic therapy. However, secondary endpoints were established: to determine whether high protein ONS influences the nutritional status, the quality of life, and the performance status. Materials and Methods: A total of 114 persons aged 40–84 years old with colorectal cancer were examined. Based on the randomization, 47 patients were qualified to the interventional group (ONS group) and 48 to Control group. To evaluate the nutritional status NRS-2002 (Nutritional Risk Screening), SGA (Subjective Global Assessment), SCRINIO (SCReenIng the Nutritional status In Oncology) Working Group classification, VAS (Visual Analog Scale) for appetite was used. FAACT (Functional Assessment of Anorexia/Cachexia Therapy) questionnaire was used for assessment of the quality of life. The health status of patients was evaluated based on the Karnofsky Performance Scale. Anthropometric measurements were done. Results: Severe complications of chemotherapy, which caused the end of treatment, a slight complication of the gastrointestinal tract such as diarrhea grade 2 according to ECOG (Eastern Cooperative Oncology Group) score regardless of the studied group, were observed. There were no statistical differences in the number and severity of the observed complications, i.e., neutropenia, leucopenia, thrombocytopenia, anemia, abdominal pain, nausea and vomiting, and diarrhea. During the follow-up the significant changes of SGA, VAS, albumin and prealbumin were observed between groups. In the ONS group an improvement in nutritional status was noticed (increased appetite VAS, p = 0.05; increased points in SGA, p = 0.015, and increased levels of albumin and prealbumin, p = 0.05). In Control group nutritional status was stable during observation. The performance status and quality of life were stable in both groups. No statistical differences between groups (ONS vs. Control) in the numbers for disqualification, resignation, delay in treatment, or dose reduction were observed. Conclusions: Results of the study did not indicate that nutritional support in precachectic oncologic patients influenced the toxicity of systemic therapy. High protein nutritional support improved nutritional status assessed by SGA, VAS for appetite, albumin, and prealbumin. The performance status and quality of life were stable throughout the observation and were not changed under the supplementation.

30 April 2023 in Cancers
Verified
Journal Article
Open access
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MSMaciej Słodkowski
Maciej Słodkowski
MWMarek Wroński
Marek Wroński
DKDominika Karkocha
Dominika Karkocha
LKLeszek Kraj
Leszek Kraj
KŚKaja Śmigielska
Kaja Śmigielska
AJAneta Jachnis-Morzy
Aneta Jachnis-Morzy
Radical resection is the only curative treatment for pancreatic cancer. However, only up to 20% of patients are considered eligible for surgical resection at the time of diagnosis. Although upfront surgery followed by adjuvant chemotherapy has become the gold standard of treatment for resectable pancreatic cancer there are numerous ongoing trials aiming to compare the clinical outcomes of various surgical strategies (e.g., upfront surgery or neoadjuvant treatment with subsequent resection). Neoadjuvant treatment followed by surgery is considered the best approach in borderline resectable pancreatic tumors. Individuals with locally advanced disease are now candidates for palliative chemo- or chemoradiotherapy; however, some patients may become eligible for resection during the course of such treatment. When metastases are found, the cancer is qualified as unresectable. It is possible to perform radical pancreatic resection with metastasectomy in selected cases of oligometastatic disease. The role of multi-visceral resection, which involves reconstruction of major mesenteric veins, is well known. Nonetheless, there are some controversies in terms of arterial resection and reconstruction. Researchers are also trying to introduce personalized treatments. The careful, preliminary selection of patients eligible for surgery and other therapies should be based on tumor biology, among other factors. Such selection may play a key role in improving survival rates in patients with pancreatic cancer.

9 February 2022 in Biology
Verified
Journal Article
Open access
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MBMaksymilian Baryła
Maksymilian Baryła
ASAleksandra Semeniuk-Wojtaś
Aleksandra Semeniuk-Wojtaś
LRLetycja Róg
Letycja Róg
LKLeszek Kraj
Leszek Kraj
MMMaciej Małyszko
Maciej Małyszko
RSRafał Stec
Rafał Stec
The tumor microenvironment is the space between healthy tissues and cancer cells, created by the extracellular matrix, blood vessels, infiltrating cells such as immune cells, and cancer-associated fibroblasts. These components constantly interact and influence each other, enabling cancer cells to survive and develop in the host organism. Accumulated intermediate metabolites favoring dysregulation and compensatory responses in the cell, called oncometabolites, provide a method of communication between cells and might also play a role in cancer growth. Here, we describe the changes in metabolic pathways that lead to accumulation of intermediate metabolites: lactate, glutamate, fumarate, and succinate in the tumor and their impact on the tumor microenvironment. These oncometabolites are not only waste products, but also link all types of cells involved in tumor survival and progression. Oncometabolites play a particularly important role in neoangiogenesis and in the infiltration of immune cells in cancer. Oncometabolites are also associated with a disrupted DNA damage response and make the tumor microenvironment more favorable for cell migration. The knowledge summarized in this article will allow for a better understanding of associations between therapeutic targets and oncometabolites, as well as the direct effects of these particles on the formation of the tumor microenvironment. In the future, targeting oncometabolites could improve treatment standards or represent a novel method for fighting cancer.

18 August 2023 in Current Oncology
Verified
Journal Article
Open access
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MOMalgorzata Osmola
Malgorzata Osmola
BGBeata Gierej
Beata Gierej
KMKatarzyna Mleczko-Sanecka
Katarzyna Mleczko-Sanecka
AJAneta Jończy
Aneta Jończy
Olga CiepielaOlga Ciepiela
Olga Ciepiela
GBGrzegorz Wladyslaw Basak
Grzegorz Wladyslaw Basak
Anemia and iron deficiency (ID) are common complications in patients with pancreatic ductal adenocarcinoma (PDAC), but their underlying causes remain unclear. This study investigated the incidence and characteristics of anemia and micronutrient deficiencies in PDAC patients before initiating chemotherapy. A total of 103 PDAC patients were included, comprising 67 in the palliative and 36 in the adjuvant groups. The overall incidence of anemia was 42.7% (n = 44), with comparable rates in both groups. Normocytic and normochromic anemia were predominant, with mild and moderate cases observed in 32% and 10.7% of the cohort, respectively. ID was evident in 51.4% of patients, with absolute ID more frequent in the adjuvant than in the palliative group (19.4% vs. 13.4%). Functional ID occurred more often in the palliative than in the adjuvant group (41.8% vs. 25%). Vitamin B12 and folate deficiency occurred in <5% (n = 5) of patients. Furthermore, 8.7% (n = 9) of patients had chronic kidney disease and anemia. To elucidate mechanisms of iron deficiency, the study explored the expression of iron regulators (hepcidin (HEP), ferroportin (FPN), and ZIP14 protein) and mitochondrial mass in PDAC tissue with immunohistochemical (IHC) staining and Perl’s Prussian blue to detect iron deposits on available tumor samples (n = 56). ZIP14 expression was significantly higher in less advanced tumors (p = 0.01) and correlated with mitochondrial mass (p < 0.001), potentially indicating its role in local iron homeostasis. However, no significant impact of tissue iron regulators on patient survival was observed. Perl’s Prussian blue staining revealed iron deposits within macrophages, but not in pancreatic duct cells. Furthermore, the GEPIA database was used to compare mRNA expression of iron regulators (HEP, FPN, and ZIP14) and other genes encoding iron transport and storage, including Transferrin Receptor Protein 1 (TfR1) and both ferritin chain subunits (FTH and FTL), in PDAC and normal pancreatic samples. FPN, TfR1, FTH, and FTL showed higher expression in tumor tissues, indicating increased iron usage by cancer. ZIP14 expression was higher in the pancreas than in PDAC and was correlated with FPN expression. The study highlights the importance of baseline iron status assessment in managing PDAC patients due to the high incidence of anemia and iron deficiency. Furthermore, ZIP14, in addition to HEP and FPN, may play a crucial role in local iron homeostasis in PDAC patients, providing valuable insights into the underlying mechanisms of iron dysregulation.

1 January 2017 in Contemporary Oncology
Verified
Journal Article
Open access
MZMonika Aleksandra Ziętarska
Monika Aleksandra Ziętarska
JKJoanna Krawczyk-Lipiec
Joanna Krawczyk-Lipiec
LKLeszek Kraj
Leszek Kraj
RZRenata Zaucha
Renata Zaucha
SMSylwia Malgorzewicz
Sylwia Malgorzewicz
Aim of the study . Cancer is usually associated with impaired nutritional status, which is one of the factors contributing to the deterioration of the results of surgery, chemotherapy, or radiotherapy. The aim of this study was the assessment of the nutritional status of patients with CRC...