Experimental oncology最新文献

The tumor microenvironment (TME) plays a critical role in tumor survival, progression, and metastasis. Нypoxia level, as an integral parameter of TME, occupies a central place in the regulation and control of all events occurring in TME. The review focuses on the findings obtained by the authors during the study of the hypoxia impact on the processes related to some microenvironmental factors in order to identify its prognostic significance regarding the course of the disease. It was shown that most microenvironmental factors are largely associated with hypoxia and involved in the processes of the tumor response to therapy. Their significance in the development of minimal residual disease and in the processes that can be affected by adipose tissue is also discussed. Therapeutic strategies based on the tumor's distinctive properties should be more highly selective in relation to the tumor, allowing the highest possible therapeutic gain for a more favorable prognosis of the disease outcome and overall survival of patients with gastric cancer. The literature data on the subject are also discussed.

Background: Lectins are carbohydrate-binding proteins with diverse biological activities, and they are increasingly recognized for their potential in cancer diagnostics and therapy. Aim of the study was to investigate the cytostatic and cytotoxic effects of the bacterial lectin of Bacillus subtilis IMV B-7724 on breast cancer (BC) cell lines of different molecular subtypes.

Materials and methods: Experiments were performed on the T47D (luminal A), MCF‑ 7 (luminal B), and MDA-MB-468 (basal, triple-negative) cell lines. Cytotoxicity was assessed by crystal violet staining and LC₅₀/LC₃₀ determination. Cytomorphological alterations were analyzed using the Romanowsky - Giemsa staining and ImageJ morphometry. A flow cytometry was applied to evaluate the cell cycle distribution and apoptosis (Annexin V/PI assay). The expression of proliferation and apoptosis regulators (Ki-67, p53, BCL-2, BAX) was examined by immunocytochemistry.

Results: The lectin exerted dose-dependent cytotoxicity across all tested cell lines, with LC₅₀ values ranging between 351-419 μg/mL. The morphological analysis revealed subtype-specific alterations, including cell rounding, nuclear condensation, and decreased cytoplasmic volume, indicative of the apoptotic process. The flow cytometry showed distinct cell cycle arrest patterns: S-phase accumulation in T47D, G2/M blockade in MCF‑ 7, and combined S- and G2/M-phase arrest in MDA-MB-468. The viability assays confirmed a significant reduction of live cells, predominantly through late apoptosis and necrosis, with the strongest effect observed in T47D cells. The immunocytochemistry demonstrated a marked downregulation of Ki-67 and BCL-2, increased p53 expression, and BAX upregulation in MCF‑ 7 cells, whereas T47D cells displayed a paradoxical BAX suppression despite the apoptotic features.

Conclusions: Lectin of B. subtilis IMV B-7724 exerts multifaceted effects on BC cells of different molecular subtypes, including the suppression of cell proliferation, activation of apoptosis, and cell cycle modulation. The observed differences between the BC cell lines suggest that the lectin efficacy depends on both the molecular profile of the cells and the mode of apoptosis regulation (p53-dependent or p53-independent), warranting further studies to identify key targets.

Background: The VNTR 4a/b (rs61722009) polymorphism in intron 4 of the NOS3 gene is crucial for various biological processes and has been linked to cancer. Evidence suggests this polymorphism affects NOS3 gene expression and may promote tumor growth in the mammary gland.

Aim: This study aimed to investigate the association between NOS3 4a/b polymorphism and breast cancer (BC) susceptibility in Iraqi women, and to evaluate the potential correlation between these genetic variants and serum cancer antigen 15-3 (CA15-3) levels as a prognostic marker.

Materials and methods: The role of the 4a/b polymorphism was examined using PCR genotyping on dNA extracted from participants, including 50 women with BC and an equal number of controls. The level of CA15-3 was measured in the patients as well.

Results: The homozygous wild-type b/b genotype may confer a protective effect against BC, with a significantly lower frequency in patients (8%) compared to controls (72%) (p < 0.01). Conversely, the heterozygous a/b and homozygous mutant a/ a genotypes were more frequent in patients (50% and 42%, respectively) than in controls (22% and 6%, respectively) (p < 0.01). Notably, the a/a genotype was significantly associated with increased BC risk (OR = 3.08, 95% CI: 1.19-5.47) and predominantly observed in the advanced pT2 stage. Additionally, the mean serum CA15-3 levels were significantly higher in patients with the a/a and a/b genotypes (15.66 U/mL and 22.91 U/mL, respectively) compared to those with the b/b genotype (6.37 U/mL) (p < 0.01).

Conclusion: The differences in genotype and allele frequencies between BC patients and healthy controls, along with the association of polymorphisms with CA15-3 levels, suggest that this genetic marker could serve as a valuable tool for risk assessment as well as prognosis in BC ptients. further investigations with larger and more diverse population samples are needed.

Background: Synchronous metastatic liver disease (SLM) in colon cancer (CC) patients is an extremely unfavorable prognostic factor. The impact of lymph node ratio (LNR) and tumor burden score (TBS) on prognosis in this subset of patients remains incompletely understood.

Aim: To assess the impact of LNR and TBS on survival in CC patients with synchronous LM who underwent staged or simultaneous surgery.

Materials and methods: A retrospective analysis of 365 patients with CC and SLM who underwent either staged or simultaneous surgical resection at the National Cancer Institute (Kyiv, Ukraine) between 2010 and 2024 was conducted. The demographic, clinicopathological, and survival data were analyzed. LNR was defined as the proportion of metastatic lymph nodes to total harvested lymph nodes, with a cutoff of 0.25. TBS was calculated using the Sasaki formula and categorized into three risk groups.

Results: A mathematical model identified TBS clusters (p < 0.04, HR = 1.8, 95% CI 1.1-2.3), the number of LM (p = 0.02, HR = 0.8, 95% CI 0.3-1.4), pN stage (p = 0.03, HR = 0.6, 95% CI 0.3-0.9), LNR (p = 0.005, HR = 3.1, 95% CI 2.2-4.2), and KRAS gene status (p = 0.01, HR = 1.1, 95% CI 1.1-1.3) as independent risk factors for overall survival.

Conclusion: Lymph node ratio and tumor burden score allow us to argue the surgical strategy choice for CC patients with synchronous liver metastases who are candidates for surgical resection. The staged surgical strategy provided better oncological outcomes in CC patients with both high LNR and TBS.

The сlose coexistence of organisms of different biological species is one of the leading principles of the organization of living matter. The interaction of microbial biofilms with adjacent tissues of the host deserves special attention. The article raises controversial issues related to the possible malignant effect of microbial biofilms.

Background: Invasion and metastasis of breast cancer (BC) critically depend on extracellular matrix (ECM) remodeling, regulated by matrix metalloproteinases (MMPs) and their endogenous tissue inhibitors (TIMPs). The dysregulation of the MMP-TIMP axis, together with the post-transcriptional control by microRNAs (miRNAs), contributes to the aggressive phenotype of BC.

Materials and methods: The expression of collagenases (MMP-1, MMP-8, MMP-13), gelatinases (MMP-2, MMP-9), TIMP1-4, and selected regulatory miRNAs (miR-34a-5p, miR-100-5p, miR-132-3p, miR-145-5p, miR-155-5p, miR-200b-5p) was analyzed by immunocytochemistry and real-time PCR in 4 human BC cell lines representing different molecular subtypes (MCF‑ 7, T47D, MDA-MB-231, MDA-MB-468).

Results: Distinct subtype-specific expression profiles were identified. At the mRNA level, the triple-negative BC cells showed the highest expression of collagenases (MMP1, MMP8, MMP13) and MMP9, whereas luminal BС cells of the MCF‑ 7 line exhibited the maximal MMP2 levels. At the protein level, collagenases predominated in the luminal BC cell lines (T47D, MCF‑ 7), while gelatinases were most abundant in MDA-MB-231. TIMP1 and TIMP3 transcripts were the highest in T47D, TIMP2 in MDA-MB-468 cells, while the TIMP3 expression in MDA-MB-231 cells was absent. miRNA profiling revealed a generally higher expression of miR-34a-5p, miR-100-5p, miR-132-3p, and miR-145-5p in the triple-negative BC cell lines, whereas MCF‑ 7 cells displayed the lowest levels except for miR-155-5p, the expression of which was maximal. The discrepancies between mRNA and protein levels suggest a miRNA-mediated post-transcriptional regulation, although not universally consistent across all MMPs.

Conclusions: The study demonstrates that the MMP-TIMP-miRNA axis exhibits subtype-specific expression patterns in the BC cell lines. The observed heterogeneity highlights the importance of post-transcriptional regulation and suggests that integrated profiling of MMPs, TIMPs, and regulatory miRNAs may provide novel insights into the invasive potential of BC and identify candidate biomarkers for clinical validation.

The study aimed to identify the clinically relevant gene variants in unresectable cutaneous melanoma samples from Ukrainian patients using NGS technology and to investigate some pharmacogenomic markers useful for the development of cancer treat- ment strategies.

Materials and methods: 30 samples of unresectable cutaneous melanomas of various localizations and differen- tiation grades were analyzed. The Ion Torrent NGS technology of targeted gene sequencing (Custom AmpliSeq™ Cancer hotspot and Pharmacogenomic panels) was applied to identify the genetic alterations, which were classifi d using franklin by Gennox database and custom pharmacogenomic Ion Reporter Software pipeline.

Results: A total of 148 different gene alterations were identifi d in 40 genes (SNVs, MNVs, INdELs) by the Cancer hotspot Panel, revealing the mutation patterns consistent with the international data. however, notable discrepancies exist, such as a high KRAS mutation rate (29.3%), predominantly in stage III tumors, suggesting their role in tumor aggressiveness and progression. We identifi d the frequent TP53 and BRAF mutations, with BRAF V600E being the most common, and observed a higher prevalence of BRAF mutations in females. TP53 mutations were prevalent (59.3%) and varied with age and sex, though their prognostic signifi ance requires further validation. A second key novel fi ding was the detection of FLT3 mutations in 22.2% of the samples, with a signifi antly higher prevalence in stage IV disease, suggesting a potential role of FLT3 in melanoma progression and warranting further investigation as a prognostic biomarker and a potential target for the existing FLT3 inhibitors. Ultimately, our pilot analysis of pharmacogenomic markers un- derscored their potential clinical utility in choosing personalized treatment decisions. for instance, the identifi ation of a patient with the rs35599367 (G/A) risk allele for adverse drug reactions underscores the value of using pharmacogenetic data to make a correct selection between approved therapies.

Conclusions: Our study presents the fi st comprehensive analysis of somatic mutations and pharmacogenomic markers in unresectable cutaneous melanoma tissue samples from Ukrainian patients. We found that while common somatic variants generally align with global trends, the mutational landscape in this cohort presents several unique features: a high KRAS mutation rate and its apparent stage-specifi prevalence, and a high FLT3 mutation rate, predominantly in stage IV tumors. further validation on a larger number of samples, as well as more exhaustive analysis employ- ing alternative methods, is necessary to substantiate these fi dings and to facilitate more effective melanoma treatment.

Background: Telomerase is a ribonucleoprotein (RNP) reverse transcriptase that replicates the ends of chromosomes, thereby maintaining genome integrity, and its inhibition may be envisioned to prevent carcinogenesis or treat cancer patients. Various approaches have been used to target hTERT, and one of the promising strategies is the use of hTERT-targeting microRNAs (miRNAs).

Aim: To investigate the interaction of miRNAs with hTERT, describing the strength, affinity, preferred binding orientation, and in vitro verification of miRNA on hTERT expression in cancer.

Materials and methods: The miRWalk, TargetScan, and miRDB databases were used for screening. Consistently, five top-hit miRNAs were found in all three databases that could interact with hTERT mRNA, namely, hsa-miR-4651, hsa-miR-608, hsa-miR-6796-5p, hsa-miR-6752-5p, and hsa-miR-6791-5p. We applied stringent in silico tools to firstly model the structures of lead miRNA and hTERT mRNA. Then docking was performed, and finally stability of miRNA-mRNA complexes was analyzed using MD simulations.

Results: The expression of the selected miRNAs was inhibited in the MCF-7 breast cancer cell line. The inhibition of hsa-miR-6796-5p was enhanced, while hsa-miR-4651 significantly reduced the expression of hTERT protein. Moreover, the inhibition of hsa-miR-4651 expression led to a reduction in melanoma and breast cancer cell proliferation.

Conclusion: The current study provided a detailed procedure for identifying and verifying miRNAs against mRNAs, as well as highlighting the differential regulation of hTERT by specific miRNAs. It demonstrated that miRNA inhibition can modulate hTERT expression and cell proliferation, with potential implications for targeted cancer therapies. The strategy used in this study could also be applied to other genes for screening potential miRNAs.

Aim: To assess the expression of MGMT (O6-methylguanine-DNA methyltransferase) gene by MGMT RNA abundance and the presence of IDH1/2 (isocitrate dehydrogenase) variants in glioblastoma (GBM) samples for predicting the efficacy of temozolomide (TMZ) treatment, recurrence risk, and patients' survival.

Materials and methods: The expression of the MGMT gene and the presence of IDH1/2 variants were assessed by RT-PCR in tumor samples from 39 patients with histologically verified GBM or diffuse astrocytoma, grade 4. The number of MGMT RNA copies was determined by the calibration curves based on the pMA-RQ plasmid with the inserted MGMT gene.

Results: The number of MGMT RNA copies in GMB samples varied broadly from 1.7 to 88,270.2 copies per 1000 cells. The patients with a low level of MGMT expression (<1000 copies) in tumors had a more favorable prognosis for the TMZ treatment compared to the patients with a high level of MGMT RNA abundance (>10,000 copies). Among the patients included in the study, a wild type of IDH1/2 was detected in 36 cases, while 3 cases were IDH1 heterozygous.

Conclusion: The level of MGMT expression is considered a significant factor for prognosing GMB patients' survival. Patients with a low level of MGMT expression are considered candidates for efficient therapy with alkylating agents.

Aim: To study the prognostic value of the lymphocyte subset distribution to predict the overall survival and its association with the clinicopathologic characteristics and treatment in patients with cancer of the oral cavity, oropharynx, and laryngopharynx.

Materials and methods: 44 patients were examined. Immunophenotyping of lymphocyte subsets was performed in peripheral blood samples using flow cytometry. The lymphocyte subset distribution was analyzed depending on the clinicopathological characteristics and treatment outcome, as well as the overall survival.

Results: The changes in CD3+ T-cells and CD3+57+ NKT counts were associated with the sex of the patients, TCRαβ+ T-cells - with the stage of the disease, CD4+8+T-cells and CD3-16+57+ NK - with the tumor size and differentiation grade, and CD3+HLA-DR+,CD8+ T-cells, and CD4+/CD8+ ratio - with lymph node involvement. The content of CD3+HLA-DR+ and TCRαβ+ T-cells, CD3-16+57+ NK, and CD3+57+ NKT differed in patients depending on the tumor location. There were changes in CD19+ and HLA-DR+ B-cells, CD3+, CD4+, CD4+25+ and TCRαβ+ T-cells, CD3-CD16+57+ NK, and CD3+57+ NKT during treatment, with the most pronounced changes after the first stage of RT. The relative number of CD3+HLA-DR+ and tumor size T4 influenced the overall survival of patients ((HR = 0.798, 95% CI, 0.658-0.967, p = 0.021) and (HR = 3.015, 95% CI, 1.303-6.975, p = 0.009), respectively).

Conclusion: Parameters of lymphocyte subsets can be promising prognostic markers.