Background: Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related deaths globally, accounting for approximately 85% of lung cancers. Although the level of diagnosis and treatment continues to improve, the patient’s prognosis is still unsatisfactory due to the high recurrence and metastasis rates. Searching for potential molecular markers is of great significance for early diagnosis, prognostic assessment and targeted treatment. Human aldehyde dehydrogenase 18 family member A1 (ALDH18A1) has been found to be associated with tumor proliferation and prognosis in a variety of cancers, but its expression and clinical significance in NSCLC are unclear. Aim: To verify the protein expression characteristics of NSCLC through immunohistochemical experiments on tissue chip, and provide theoretical basis for molecular diagnosis and targeted treatment of NSCLC. Materials and Methods: In this study, ALDH18A1 protein expression was determined in 80 cases of lung squamous cell carcinoma (LUSC), 52 cases of adenocarcinoma (LUAD), and adjacent tissues of combined tumors using TMA and IHC methods. Indirect IHC staining was performed on 4-μm-thick sections, and semiquantitative evaluation was performed based on the staining intensity and percentage of positive cells. ALDH18A1 expression was analyzed in relation to clinicopathological parameters (age, sex, TNM stage, clinical grade) and patient survival. Result: ALDH18A1 was highly expressed in the tumor tissues of 132 cases of LBCL, but was low or absent in the surrounding normal tissues. In LUSC, high ALDH18A1 expression was significantly associated with poor tissue differentiation (P<0.001), advanced TNM stage (P<0.001), distant metastasis (P=0.0327) and tumor size (P=0.0166). In LUAD, it was associated with poor tissue differentiation (P<0.001), advanced TNM stage (P<0.001) and tumor size (P=0.00302). According to Kaplan–Meier analysis, OS of patients with high ALDH18A1 expression was significantly shorter than that of those with low expression (LUSC: P=0.0014, LUAD: P<0.0001). The results showed that high ALDH18A1 expression was strongly associated with the infectivity of HLH and poor prognosis. Conclusion ALDH18A1 is highly expressed in NSCLC tissue and is related to tumor progression. It may serve as a potential molecular marker and treatment target, providing reference for the diagnosis and prognosis of NSCLC.

Background: Non-small cell lung cancer (NSCLC) is the most common pathological type of lung cancer, and its incidence and mortality rates have long ranked among the highest of malignant tumors worldwide. Through bioinformatics analysis, this study identified the oncogene ALDH18A1, which is closely related to the development of NSCLC. Recent studies have shown that ALDH18A1 is highly expressed in various malignant tumors and participates in regulating biological processes such as cell viability and proliferation. However, its specific role and molecular mechanism in NSCLC remain unclear. Aim: To investigate the expression characteristics of ALDH18A1 in NSCLC cells and its effects on cell viability and proliferation. Materials and Methods: The expression levels of ALDH18A1 in various NSCLC cell lines and normal lung cells were detected by real-time quantitative PCR (qPCR) and Western blot. NSCLC cell lines with high ALDH18A1 expression were selected, and ALDH18A1 was knocked down using siRNA technology. The effects of ALDH18A1 downregulation on cell viability and proliferation were evaluated using CCK-8 assays and colony formation assays, and the experimental results were analyzed using statistical methods. Result: The expression level of ALDH18A1 in NSCLC cell lines was significantly higher than that in normal lung cells, and the expression was particularly significant in H1975 cells. Knockdown of ALDH18A1 expression significantly reduced the viability and proliferation capacity of NSCLC cells, and the difference was statistically significant (P<0.05). Conclusion ALDH18A1 is highly expressed in NSCLC cells, and its downregulation can significantly inhibit the viability and proliferation of tumor cells, suggesting that ALDH18A1 plays a pro-tumor role in the occurrence and development of NSCLC and has research value as a potential oncogene and therapeutic target.

Background: Oral squamous cell carcinoma (OSCC) is the most common subtype of head and neck squamous cell carcinoma (HNSC) and poses a serious threat to human health. The molecular mechanisms underlying the initiation and progression of OSCC are highly complex. Although notable advances have been made in diagnostic and therapeutic technologies in recent years, the five-year survival rate of patients has not improved substantially. Therefore, in-depth investigation of the molecular mechanisms of OSCC, identification of potential diagnostic and therapeutic biomarkers, and development of effective treatment strategies have become critical directions in current research. Aim: To investigate the relationship between the prognosis of HNSC/OSCC and the m7G-related lncRNA GSEC. Materials and Methods: RNA-seq transcriptome data and clinical data for HNSC were downloaded from The Cancer Genome Atlas (TCGA). Differential expression analysis of lncRNAs was performed, and differentially expressed lncRNAs were selected. Univariate Cox regression analysis was used to screen lncRNAs associated with prognosis. The random forest algorithm was employed to rank the importance of differentially expressed lncRNAs, and the top 50 lncRNAs were selected. Twenty-nine m7G-related genes were obtained from published literature. m7G-related lncRNAs were screened based on Pearson correlation analysis. The intersection of these results was taken to identify diagnostic biomarker m7G-related lncRNAs. The UALCAN database was used to analyze the expression of target m7G-related lncRNA in HNSC/OSCC. cBioPortal was used to analyze the gene mutation profile of GSEC in HNSC. Co-expressed genes of the target lncRNA in HNSC were collected via cBioPortal, filtering for genes with FDR<0.05 and R>0.4. GO/KEGG enrichment analysis was performed using the Metascape database. Immunohistochemical expression levels of the m7G-related gene were analyzed using the Human Protein Atlas (HPA) database. The expression level of the m7G-related lncRNA in cells was detected using qRT-PCR. Result: A total of 3,618 differentially expressed lncRNAs were identified in HNSC from the TCGA database, including 2,421 upregulated and 1,197 downregulated genes. Univariate Cox regression analysis showed that 1,306 lncRNAs were significantly associated with HNSC patient prognosis (P<0.05). The random forest algorithm ranked the top 50 important lncRNAs. Pearson correlation analysis (|correlation coefficient|>0.5, P<0.001) identified 310 m7G-related lncRNAs. Taking the intersection with lncRNAs significant in the random forest and univariate Cox regression analyses revealed that the m7G-related lncRNA GSEC has significant diagnostic value in HNSC, with DCPS identified as the m7G-related gene for lncRNA GSEC. GSEC/DCPS were significantly upregulated in HNSC/OSCC (P<0.05). High expression of GSEC showed value in predicting poor outcomes in OSCC (AUC=0.937). Analysis of the mutation spectrum of the target gene GSEC indicated that GSEC undergoes genetic mutations in HNSC, including amplification and altered mRNA expression levels. Enrichment analysis of GSEC co-expressed genes in HNSC (FDR<0.05, R>0.4) revealed that GO terms were primarily enriched in the endoplasmic reticulum lumen, glycoprotein metabolic process, and collagen fibril organization. KEGG pathways were mainly enriched in Protein processing in endoplasmic reticulum, Glycosaminoglycan biosynthesis-heparan sulfate/heparin, and Lysine degradation. Immunohistochemical analysis revealed high expression of DCPS, the m7G-related protein within the GSEC, in OSCC tissues compared to normal mucosal tissues. Further qRT-PCR detection demonstrated that GSEC is upregulated in OSCC cell lines relative to NHOK cells. Among the OSCC cell lines examined, CAL-27 exhibited the most pronounced upregulation of GSEC expression compared to SCC-4 and HSC-2 cells. Conclusion Bioinformatics analysis in this study revealed significant upregulation of the m7G-related GSEC/DCPS in HNSC/OSCC. Moreover, GSEC/DCPS expression was correlated with the prognosis of HNSC/OSCC. These findings suggest that GSEC/DCPS may serve as a novel molecular target for the diagnosis and treatment of HNSC/OSCC.

Background: Anterior cruciate ligament (ACL) rupture is one of the most common sports-related knee injuries among young and physically active individuals, often leading to knee instability, functional impairment, and delayed return to sports. Although hamstring tendon (HT) autografts are widely used in ACL reconstruction, the optimal graft choice remains controversial. The superficial rectus femoris (SRF) tendon has recently emerged as a potential alternative autograft with favorable biomechanical properties. This study aimed to compare the clinical stability and functional outcomes of ACL reconstruction using SRF and HT autografts. Aim: This study aimed to characterize the epidemiology and risk profile of knee joint injuries in Mongolia over a 10-year period, and to evaluate the comparative clinical efficacy and functional recovery following ACL reconstruction using hamstring tendon (HT) versus superficial rectus femoris (SRF) autografts. Materials and Methods: A randomized parallel-group clinical study was conducted at the Sports Injury Center of the National Trauma and Orthopedic Research Center. Fifty patients aged ≥18 years with complete ACL rupture were enrolled and randomly assigned to undergo ACL reconstruction using either a superficial rectus femoris autograft (SRF group, n=25) or a hamstring tendon autograft (HT group, n=25). The primary outcome was mechanical knee stability. Secondary outcomes included functional performance assessed using three-dimensional motion analysis, as well as patient-reported outcomes measured using the International Knee Documentation Committee (IKDC) and Lysholm scores. Clinical and functional assessments were performed preoperatively and at 1, 3 and 6-month postoperative follow-up visits. Comparative analyses were conducted to evaluate differences in recovery patterns between the two groups. Result: Patients in the SRF group demonstrated significantly lower early postoperative pain levels and faster functional recovery compared with the HT group (p<0.01). Three-dimensional motion analysis revealed earlier restoration of limb symmetry and improved dynamic knee stability in the SRF group during the early postoperative period. These objective biomechanical findings supported the clinical observation of accelerated rehabilitation following ACL reconstruction using SRF autografts. At six months postoperatively, however, no statistically significant differences were observed between the SRF and HT groups in terms of mechanical knee stability or patient-reported functional outcomes. Conclusion ACL reconstruction using a superficial rectus femoris autograft demonstrated superior early functional recovery compared with the traditional hamstring autograft while achieving comparable short-term clinical stability. These findings suggest that the SRF autograft may represent a promising alternative graft option for patients requiring accelerated rehabilitation and earlier return to physical activity.

Background: Renal cell carcinoma (RCC) accounts for 85–90% of all primary renal malignancies in adults and 1–3% of all cancers worldwide, with incidence rising steadily year by year. Clear cell (ccRCC), papillary (pRCC), and chromophobe (chRCC) subtypes differ significantly in genetic alterations, biological behavior, and treatment response, making preoperative subtype identification clinically important. Conventional qualitative CT assessment is limited, and contrast-enhanced CT-based radiomics may represent a novel diagnostic approach. Aim: To develop a model for preoperative differentiation of ccRCC from non-ccRCC subtypes using contrast-enhanced CT-based radiomics, and to evaluate its diagnostic performance through internal and external validation. Materials and Methods: A retrospective study was conducted on 121 patients with histopathologically confirmed RCC treated at the Urology–Andrology Center of the First Central Hospital of Mongolia between 2021 and 2024. Patients were categorized into ccRCC (n=84) and non-ccRCC (n=37) groups. Tumor segmentation was performed on corticomedullary phase CT images using 3D Slicer software, and a total of 122 radiomic features were extracted, including first-order uniformity, gray-level co-occurrence matrix (GLCM), gray-level run-length matrix (GLRLM), shape flatness, and GLCM maximum probability. Diagnostic performance was assessed by ROC analysis, and model generalizability was evaluated through external validation (n=73). Results: GLRLM demonstrated a statistically significant difference between the ccRCC (mean 0.1230) and non-ccRCC (mean 0.0170) groups (p<0.001). ROC analysis yielded an optimal cut-off value of 0.1493 for GLRLM, with an internal validation AUC of 0.9103, sensitivity of 83.3%, and specificity of 92.3% (p<0.01). External validation (n=73) achieved an AUC of 0.860 and an accuracy of 86.0%, confirming the model’s generalizability. First-order uniformity (AUC=0.880) and variance (AUC=0.862) showed comparable discriminative performance to GLRLM, whereas flatness (AUC=0.584) and GLCM Imc2 (AUC=0.621) demonstrated relatively poor discriminative ability. Confusion matrix analysis yielded an accuracy of 86.0% in both internal and external validation cohorts. Conclusion Non-invasive CT-based radiomics demonstrates the ability to accurately differentiate RCC subtypes preoperatively with high precision (AUC=0.92), as confirmed by both internal and external validation.

Background: Early and accurate differentiation of benign and malignant breast nodules is crucial for determining appropriate therapeutic strategies. Recently, artificial intelligence (AI)-based diagnostic systems have been increasingly utilized to enhance the diagnostic performance of ultrasound imaging. Aim: To evaluate the diagnostic value of artificial intelligence-based ultrasound (AI-US) in differentiating benign and malignant breast nodules and to compare its performance with conventional ultrasound (US). Materials and Methods: This retrospective study included 101 patients with 103 breast nodules (58 malignant, 45 benign) confirmed by histopathological analysis (biopsy or surgery). Diagnostic performance was evaluated across three groups: 1) Conventional ultrasound (US), 2) AI system (AI group), and 3) Combined US and AI system (US+AI group). Sensitivity (SE), specificity (SP), accuracy (ACC), positive predictive value (PPV), negative predictive value (NPV), and the area under the ROC curve (AUC) were calculated and compared. Results: Of the 103 nodules, 56.3% were malignant and 43.7% were benign. The AI group demonstrated higher diagnostic metrics than the US group—SE (82.76%), SP (80.00%), ACC (81.55%), and AUC (0.814)—though the difference was not statistically significant (p>0.05). However, the combined US+AI group showed significant improvement, reaching an SE of 87.93%, SP of 86.67%, ACC of 87.38%, and an AUC of 0.874. These results were statistically superior to the conventional US group (p<0.05). Conclusion The AI-based ultrasound diagnostic system significantly improves the accuracy of differentiating breast nodules. This technology serves as a reliable decision-support tool, particularly for reducing diagnostic errors among less experienced physicians and minimizing unnecessary invasive biopsies.

Background: Colorectal cancer (CRC) is one of the leading causes of cancer-related morbidity and mortality worldwide and develops through the accumulation of genetic alterations involving multiple genes. In Mongolia, the substantial burden of CRC, limited treatment options, and scarcity of studies investigating its molecular genetic characteristics highlight the need to improve molecular diagnostics and expand personalized treatment options. Aim: To identify genetic variants in tumor tissues from patients with CRC and compare them with variants detected in matched adjacent normal tissues. Materials and Methods: This cross-sectional study was conducted between August 2023 and May 2024 in collaboration with the National Cancer Center of Mongolia, the Mongolian Institute of Human Genetics, and Happy Veritas Hospital. Eleven patients who underwent surgical treatment for CRC at the Department of General Surgery were enrolled. Paired tumor and adjacent normal tissue samples were collected from each patient and analyzed. Targeted next-generation sequencing (NGS) was performed using the MGISEQ-200 platform, covering 2,881 targeted positions across 53 cancer-associated genes. Sequencing data were processed through a bioinformatics pipeline involving quality control, alignment to the reference genome, variant calling, and filtering. BWA-MEM, GATK Mutect2, and Variant Effect Predictor (VEP) were used to identify and annotate genetic variants. Variants were comparatively evaluated according to their occurrence in tumor and adjacent normal tissues, potential functional consequences, and clinical significance. Results: A total of 60 genetic variant observations were identified across 11 paired CRC and adjacent normal tissue samples, including 56 single-nucleotide variants (SNVs; 93.3%) and four insertions or deletions (INDELs; 6.7%). Of these, 36 observations (60.0%) were recorded in tumor tissues and 24 (40.0%) in adjacent normal tissues. Eleven amino acid-altering variants were identified in tumor tissues. Variants in PDGFRA (90.9%), TP53 (54.5%), APC (36.4%), PTEN (27.3%), KIT (18.2%), and KRAS (9.1%) were detected in tumor tissues. The frequencies of variants in PDGFRA, TP53, and PTEN were higher in tumor tissues than in adjacent normal tissues, although the differences were not statistically significant (p > 0.05; FDR ≥ 0.75). Variants detected in APC, KRAS, TP53, PTEN, and MLH1 were associated with molecular pathways involved in colorectal carcinogenesis, including Wnt/β-catenin, MAPK, p53, PI3K–AKT–mTOR, and DNA mismatch repair pathways. The KRAS p.Gly13Asp (G13D) variant was identified as a clinically relevant alteration for evaluating response to anti-EGFR targeted therapy. Conclusion Variants in PDGFRA, TP53, and PTEN were more frequently observed in CRC tissues than in adjacent normal tissues; however, the differences were not statistically significant. Variants in KRAS, KIT, and CDKN2A were detected exclusively in tumor tissues. The KRAS p.Gly13Asp variant may have clinical relevance in evaluating the selection of anti-EGFR targeted therapy.

Background: A 2024 study by the National Statistical Office of Mongolia indicate an incidence rate of 38.8 per 100 000 population, with a total of 8169 new cancer cases diagnosed, of which 16.2% are gastric cancers. Notably, 64.4% of these diagnoses are made at advanced stages.2 Surgical intervention remains one of the most effective treatments for gastric cancer. Early-stage surgery confers a 5-year survival rate of 60-80%, whereas late-stage diagnosis reduces this to 18-50%.5 This study aims to investigate the causes, types, and contributing factors of postgastrectomy anemia in patients undergoing surgery for gastric cancer in Mongolia, where no prior study has been conducted on this topic. Methods: This retrospective study analyzed all patients who underwent gastric cancer surgery at the National Cancer Center of Mongolia from 2022 to 2024. Data on demographics, lifestyle factors, clinical signs of anemia, and comorbidities were collected from medical records and confirmed by direct examination. Results: A total of 788 patients who underwent surgery for gastric cancer were included in the study, of whom 70.5% were male and 29.5% female, aged 22–70 years (mean age 46 years). Among the total cases, 461 patients underwent total gastrectomy, 128 had distal gastrectomy with gastrojejunal anastomosis, 39 underwent partial gastrectomy, 3 had gastrectomy with duodenal anastomosis, 5 underwent gastrectomy with esophagogastric anastomosis, and 6 underwent bypass procedures. Conclusions Postoperative monitoring after gastric surgery was insufficient, and there was a tendency for anemia to progress.

Background: The average age at menarche (AAM) among girls is influenced by various factors, including the socioeconomic status of the country, geographical location, and anthropometric characteristics. In Mongolia, limited research has been conducted on this topic Aim: This study aimed to compare the mean age at menarche among girls living in Bayanzürkh District of Ulaanbaatar and those in Uvs Province. Materials and Methods: A cross-sectional study was conducted between April and June 2025. The study participants included schoolgirls aged 8 years and older from general education schools located in Bayanzürkh District and Uvs Province. Statistical analyses were performed using R version 4.5.1 (RStudio 2025.05.1-513) Results: A total of 486 girls participated in the study. The mean age at menarche among the participants was 12.23±1.29 years. The mean age at menarche among girls aged 8–18 years in Bayanzürkh District was 11.84±1.19 years, while that among girls aged 8–18 years in Uvs Province was 12.97±1.15 years. Thus, girls in Bayanzürkh District experienced menarche 1.13 years earlier on average than those in Uvs Province. The difference in mean AAM between urban (Ulaanbaatar) and rural (Uvs Province) girls was statistically significant (p<0.0001). Conclusion The mean age at menarche among girls residing in Bayanzürkh District was significantly lower than that of girls living in Uvs Province, indicating a tendency toward earlier onset of menarche in urban areas.

Background: Total knee replacement arthroplasty (TKA) is an essential surgical treatment method performed when the cartilage surfaces of the knee joint undergo irreversible changes due to aging, trauma, genetics, or lifestyle factors. In our country, approximately 2.500 knee replacement surgeries are performed annually. Aim: To investigate the Lysholm scores of patients who underwent total knee replacement arthroplasty and the factors influencing these scores. Materials and Methods: This study was conducted using a retrospective cohort study design. The research was carried out at the First Central Hospital of the country, involving 186 patients who visited the Department of Joint Center from January 2007 to May 2023. Participants provided demographic data, information on comorbidities, alcohol and tobacco use, physical activity, and lifestyle factors through a 56-question survey, divided into two groups. The stability and function of the knee joint were assessed using the Lysholm assessment. A score of 95-100 indicated excellent, 84-94 good, 65-83 moderate, and less than 65 poor. Statistical analysis of the results was performed using SPSS version 26.0. Results: Out of 185 participants, the mean age was 71.83±7.83 years, with 18.9% (n=35) males and 81.1% (n=150) females. The demographic factors such as gender, age group, BMI, and years after surgery were significantly associated with the Lysholm score (p=0.001). Logistic regression analysis identified that age (OR, 2.014; 95% CI, 1.620-1.659; p=0.001), excess weight (OR, 1.328; p=0.001; 95% CI, 0.469-3.765), and years after surgery (OR, 1.194; 95% CI, 0.533- 2.676; p=0.037) were factors influencing the scores Conclusion 037) were factors influencing the scores. Conclusion: The number of years after total knee replacement arthroplasty and patient age significantly affected Lysholm evaluation scores