Ki-67 Positivity Research Articles

Single-cell sequencing analysis revealed that NEAT1 was a potential biomarker and therapeutic target of prostate cancer.

Prostate cancer (PCa) usually manifests atypical symptoms in the early stage, and once symptoms appear, most PCa patients have developed to the advanced stage, failing to undergo radical surgery. In this study, PCa occurrence-related biomarkers were explored based on single-cell RNA sequencing (scRNA-seq) data. scRNA-seq data of prostate normal (Normal), benign prostatic hyperplasia (BPH), and PCa (Tumor) samples were acquired from the Gene Expression Omnibus (GEO). Cellular subsets associated with PCa occurrence were obtained using cell annotation. Additionally, the mRNA expression of nuclear enriched abundant transcript 1 (NEAT1) was detected by quantitative real-time PCR (qRT-PCR). The effects of NEAT1 on cell proliferation and apoptosis were analyzed by 5-ethynyl-2-deoxyuridine (EdU) and flow cytometry. Subsequently, cell-derived xenograft (CDX) models were constructed and divided into the LV-NC and LV-shNEAT1 groups. After the tumor tissues of CDX model mice in each group were extracted, the cell growth and Ki67 expression were observed separately using hematoxylin-eosin (H&E) staining and immunohistochemistry (IHC). Ten cellular subsets were obtained via cell annotation, and significantly differential changes were observed between Basal intermediate and Luminal during the course of BPH to PCa. NEAT1-Luminal was highly recruited in the Tumor group with low stemness and high malignancy scores. Matrix metallopeptidase 7 (MMP7)- keratin 17 (KRT17)-Basal intermediate had high ratios in the Tumor group with low stemness and high malignancy scores. The results of pseudotime analysis revealed that NEAT1-Luminal in the Tumor group were consistently distributed with tumor stage cells. In vitro assays showed that NEAT1 expression was elevated in PCa cells, and NEAT1 knockdown could inhibit cell proliferation and induce apoptosis. CDX assays indicated that silencing NEAT1 could reduce the growth rate of PCa tumor volume in CDX model mice. H&E staining results showed that nuclei of tumor cells were reduced and exhibited lighter color in the LV-shNEAT1 group compared with the LV-NC group. IHC results showed that Ki67 positivity was significantly lower in the LV-shNEAT1 group than in the LV-NC group. NEAT1 expression is increased in PCa, and NEAT1 can be a potential biomarker and therapeutic target for PCa.

Immunohistochemical Expression of Cyclin D1 in Invasive Breast Carcinoma

Objective: This study was conducted to determine the immunohistochemical expression of cyclin D1 in invasive breast carcinoma and its association with already established prognostic parameters like estrogen receptor (ER), progesterone receptor (PR), HER2/Neu, and Ki67 status. Study Design & Setting: Cross sectional Observational. Department of Pathology, Armed Forces Institute of Pathology, Rawalpindi Methodology: The study included 350 cases of invasive breast cancer diagnosed between January 2023 and December 2023. Data collected included patient age, histological subtype, molecular subtypes, tumor size, and the presence of estrogen (ER) and progesterone (PR) receptors, as well as HER2/Neu and Ki67 status. Patients who had undergone chemotherapy, received radiation to the breasts, or experienced relapse were excluded from the study. Immunohistochemistry was conducted using a Cyclin D1 antibody to assess Cyclin D1 expression in tissue samples. The expression levels were categorized as negative, weak, moderate, strong staining in tumor cells. Data analysis was performed using SPSS 29.0, and statistical comparisons were made between Cyclin D1 staining and ER, PR, HER2/Neu, and Ki67 status. Results: Cyclin D1 moderate to strong staining was seen in 173/352 (49.14%) cases of invasive BC. Cyclin D1 expression was slightly statistically significantly associated with ER (x2 = 7.78, P value <0.051) and Ki67 positivity (÷2 = 7.27, P value <0.064). Conclusion: Cyclin D1 has the potential to serve as a prognostic marker. Incorporating it into the routine IHC workup for breast cancer could enhance patient management, especially with the development of new targeted therapies that inhibit the Cyclin D-CDK4/6 axis.

The significance of risk stratification through nomogram-based assessment in determining postmastectomy radiotherapy for patients diagnosed with pT1 − 2N1M0 breast cancer

ObjectiveTo explore the high-risk factors affecting the prognosis of pT1 − 2N1M0 patients after mastectomy, establish a nomogram prediction model, and screen the radiotherapy benefit population.MethodThe clinical data of 936 patients with pT1 − 2N1M0 who underwent mastectomy in the fourth hospital of Hebei Medical University from 2010 to 2016 were retrospectively analyzed. There were 583 patients received postmastectomy radiotherapy(PMRT), and 325 patients without PMRT. Group imbalances were mitigated using the propensity score matching (PSM) method, and the log-rank test was employed to compare overall survival (OS) and disease-free survival (DFS) between the cohorts. The efficacy of PMRT across various risk groups was evaluated using a nomogram model.ResultThe median follow-up period was 98 months, Patients who received PMRT demonstrated significantly improved 5-year and 8-year OS and DFS compared to those who did not (P < 0.001). Multivariate analysis revealed that age, primary tumor site, positive lymph node, stage, and Ki-67 level independently influenced OS, while age, primary tumor site, and stage independently affected DFS. PMRT drastically enhanced OS in the high-risk group (P = 0.001), but did not confer benefits in the low-risk and intermediate risk groups (P = 0.057, P = 0.099). PMRT led to a significant improvement in disease-free survival (DFS) among patients in the intermediate and high-risk groups (P = 0.036, P = 0.001), whereas the low-risk group did not experience a significant benefit (P = 0.475).ConclusionAge ≤ 40 years, tumor located in the inner quadrant or central area, T2 stage, 2–3 lymph nodes metastasis, and Ki67 > 30% were the high-risk factors affecting the prognosis of this cohort of patients. In OS nomogram, patients with a risk score of 149 or higher who received PMRT exhibited improved OS. Similarly, in DFS nomogram, patients with a risk score of 123 or higher who received PMRT demonstrated enhanced DFS.

PPARγ and C/EBPα enable adipocyte differentiation upon inhibition of histone methyltransferase PRC2 in malignant tumors

Loss of terminal differentiation is a hallmark of cancer and offers a potential mechanism for differentiation therapy. Polycomb Repressive Complex 2 (PRC2) serves as the methyltransferase for K27 of histone H3 that is crucial in development. While PRC2 inhibitors show promise in treating various cancers, the underlying mechanisms remain incompletely understood. Here, we demonstrated that the inhibition or depletion of PRC2 enhanced adipocyte differentiation in malignant rhabdoid tumors (MRTs) and mesenchymal stem cells (MSCs), through upregulation of PPARG and CEBPA. Mechanistically, PRC2 directly represses their transcription through H3K27 methylation, as both genes exhibit a bivalent state in MSCs. Knockout of PPARG compromised C/EBPα expression and impeded the PRC2 inhibitor-induced differentiation into adipocytes. Furthermore, the combination of the PPARγ agonist rosiglitazone and the PRC2 inhibitor MAK683 exhibited a higher inhibition on Ki67 positivity in tumor xenograft compared to MAK683 alone. High CEBPA, PLIN1 and FABP4 levels positively correlated with favorable prognosis in sarcoma patients in TCGA cohort. Together, these findings unveil an epigenetic regulatory mechanism for PPARG and highlight the essential role of PPARγ and C/EBPα in the adipocyte differentiation of MRTs and sarcomas with a potential clinical implication.

Flow cytometric analysis for Ki67 assessment in formalin-fixed paraffin-embedded breast cancer tissue

BackgroundPathologists commonly employ the Ki67 immunohistochemistry labelling index (LI) when deciding appropriate therapeutic strategies for patients with breast cancer. However, despite several attempts at standardizing the Ki67 LI, inter-observer and inter-laboratory bias remain problematic. We developed a flow cytometric assay that employed tissue dissociation, enzymatic treatment and a gating process to analyse Ki67 in formalin-fixed paraffin-embedded (FFPE) breast cancer tissue.ResultsWe demonstrated that mechanical homogenizations combined with thrombin treatment can be used to recover efficiently intact single-cell nuclei from FFPE breast cancer tissue. Ki67 in the recovered cell nuclei retained reactivity against the MIB-1 antibody, which has been widely used in clinical settings. Additionally, since the method did not alter the nucleoskeletal structure of tissues, the nuclei of cancer cells can be enriched in data analysis based on differences in size and complexity of nuclei of lymphocytes and normal mammary cells. In a clinical study using the developed protocol, Ki67 positivity was correlated with the Ki67 LI obtained by hot spot analysis by a pathologist in Japan (rho = 0.756, P < 0.0001). The number of cancer cell nuclei subjected to the analysis in our assay was more than twice the number routinely checked by pathologists in clinical settings.ConclusionsThe findings of this study showed the application of this new flow cytometry method could potentially be used to standardize Ki67 assessments in breast cancer.

Unveiling the hidden link: fungi and HPV in cervical lesions.

Cervical cancer, primarily driven by high-risk human papillomavirus (HR-HPV) infection, ranks as the second most common cancer globally. Understanding combined infections' role, including Cervical fungi, is crucial in cervical carcinogenesis. This study aims to explore the potential correlation between HR-HPV, cervical fungi, and cervical cancer, while adjusting for various factors. The study population comprised patients undergoing colposcopy and conization due to abnormal cervical screening results. Clinical data including age, gravidity, HPV (human papillomavirus) genotypes, cervical pathology, and p16/Ki67 expression were extracted. Cervical TCT (ThinPrep Pap Test) and HPV testing are utilized for screening cervical lesions, with fungal presence suggested by TCT results. 5,528 participants were included in this study. Statistical analyses investigated associations between HPV/fungi co-infection and cervical lesions, employing multinomial logistic regression and interaction analysis. Co-infection with fungi and HPV may decrease the risk of cervical lesions compared to HPV infection alone. In the co-infection group, compared with HPV infection alone, the risk of low-grade squamous intraepithelial lesions (LSIL) was reduced by 27% (OR = 0.73, 95% CI: 0.59-0.90), the risk of high-grade squamous intraepithelial lesions (HSIL) was reduced by 35% (OR = 0.65, 95% CI: 0.51-0.82), and the risk of cervical cancer was reduced by 43% (OR = 0.57, 95% CI: 0.35-0.92). The interaction analysis revealed a negative interaction between fungal and HPV infections in the development of cervical cancer (RERI = -6.25, AP = -0.79, SI = 0.52), HSIL (RERI = -19.15, AP = -0.37, SI = 0.72) and LSIL (RERI = -1.87, AP = -0.33, SI = 0.71), suggesting a sub-additive effect, where the combined effect of the two infections was less than the sum of their individual effects. This indicates that fungal infection may attenuate the promoting effect of HPV on cervical lesions. In exploring the potential mechanism, we found that the co-infection group had significantly lower p16 positivity (54.6%) compared to the HPV-only group (60.2%) (p = 0.004), while there was no statistically significant difference in Ki67 positivity. This study unveils the intricate relationship between cervical fungi and HPV in cervical lesions. Co-infection with fungi and HPV against cervical lesions compared to HPV infection alone, indicating a novel clinical interaction. Lower p16 positivity in co-infection hints at a protective mechanism, urging further exploration.

Correlation and predictive value of pathological complete response and ultrasound characteristic parameters in neoadjuvant chemotherapy for breast.

Breast cancer ranks as one of the most prevalent malignant tumors among women, significantly endangering their health and lives. While radical surgery has been a pivotal method for halting disease progression, it alone is insufficient for enhancing the quality of life for patients. To investigate the correlation between ultrasound characteristic parameters of breast cancer lesions and clinical efficacy in patients undergoing neoadjuvant chemotherapy (NAC). Employing a case-control study design, this research involved 178 breast cancer patients treated with NAC at our hospital from July 2019 to June 2022. According to the Miller-Payne grading system, the pathological response, i.e. efficacy, of the NAC in the initial breast lesion after NAC was evaluated. Of these, 59 patients achieved a pathological complete response (PCR), while 119 did not (non-PCR group). Ultrasound characteristics prior to NAC were compared between these groups, and the association of various factors with NAC efficacy was analyzed using univariate and multivariate approaches. In the PCR group, the incidence of posterior echo attenuation, lesion diameter ≥ 2.0 cm, and Alder blood flow grade ≥ II were significantly lower compared to the non-PCR group (P < 0.05). The area under the curve values for predicting NAC efficacy using posterior echo attenuation, lesion diameter, and Alder grade were 0.604, 0.603, and 0.583, respectively. Also, rates of pathological stage II, lymph node metastasis, vascular invasion, and positive Ki-67 expression were significantly lower in the PCR group (P < 0.05). Logistic regression analysis identified posterior echo attenuation, lesion diameter ≥ 2.0 cm, Alder blood flow grade ≥ II, pathological stage III, vascular invasion, and positive Ki-67 expression as independent predictors of poor response to NAC in breast cancer patients (P < 0.05). While ultrasound characteristics such as posterior echo attenuation, lesion diameter ≥ 2.0 cm, and Alder blood flow grade ≥ II exhibit limited predictive value for NAC efficacy, they are significantly associated with poor response to NAC in breast cancer patients.

The Overexpressed MicroRNAs miRs-182, 155, 493, 454, and U6 snRNA and Underexpressed let-7c, miR-328, and miR-451a as Potential Biomarkers in Invasive Breast Cancer and Their Clinicopathological Significance.

Breast cancer comprises the leading cause of cancer-related death in women. MicroRNAs (miRNAs) have emerged as important factors with concern to carcinogenesis and have potential for use as biomarkers. This study provides a comprehensive evaluation of the microRNA expression in invasive breast carcinoma of no special type tissues compared with benign tissues via large-scale screening and the candidate-specific validation of 15 miRNAs and U6 snRNA applying qPCR and the examination of clinicopathological data. Of the six downregulated miRNAs, let-7c was identified as the most promising miRNA biomarker and its lower expression was linked with Ki-67 positivity, luminal B versus luminal A samples, multifocality, lymph node metastasis, and inferior PFS. Of the 9 upregulated sncRNAs, the data on U6 snRNA, miR-493 and miR-454 highlighted their potential oncogenic functions. An elevated U6 snRNA expression was associated with the tumor grade, Ki-67 positivity, luminal B versus A samples, lymph node metastasis, and worsened PFS (and OS) outcomes. An elevated miR-454 expression was detected in higher grades, Ki-67 positive and luminal B versus A samples. Higher miR-493 levels were noted for the tumor stage (and grade) and worse patient outcomes (PFS, OS). The data also suggested that miR-451a and miR-328 may have tumor suppressor roles, and miR-182 and miR-200c pro-oncogenic functions, while the remaining sncRNAs did not evince any significant associations. We showed particular microRNAs and U6 snRNA as differentially expressed between tumors and benign tissues and associated with clinicopathological parameters, thus potentially corresponding with important roles in breast carcinogenesis. Their importance should be further investigated and evaluated in follow-up studies to reveal their potential in clinical practice.

LINC-PINT plays an anti-tumor role in nasopharyngeal carcinoma by binding to XRCC6 and affecting its function

BackgroundLINC-PINT was downregulated in nasopharyngeal carcinoma (NPC) and correlated with treatment efficiency of NPC. However, the underlying mechanism of LINC-PINT in NPC has not yet been fully explored. MethodWe used CellTiter luminescent assay, clone formation assay, Hoechst staining, and SYTO-9/PI staining to examine cell viability and cell apoptosis regulated by LINC-PINT in NPC cells. Xenograft tumor model, HE staining, Ki67 staining, and TUNEL assay were conducted to assess the role of LINC-PINT in vivo. Bioinformatics and RNA immunoprecipitation assay was performed to identify the binding protein of LINC-PINT. Fluorescence in situ hybridization and immunofluorescence were utilized to measure the colocalization of XRCC6 with LINC-PINT and DNA-PKcs. Mito-Tracker red CMXRos staining was used to label mitochondria in cells specifically. ResultWe found LINC-PINT was downregulated in many tumors (including NPC) and associated with poor prognosis. The cell viability was significantly inhibited and cell apoptosis was remarkably promoted in LINC-PINT overexpressed cells in contrast to control cells. The growth of tumor xenografts was significantly suppressed and the tumor weight was significantly decreased in LINC-PINT overexpression group compared to the control group. Correspondingly, the positive Ki67 foci was decreased while TUNEL foci was increased in LINC-PINT overexpression group. Mechanically, we verified XRCC6 as a new binding protein of LINC-PINT through RNA binding domains prediction, RIP and colocalization of LINC-PINT and XRCC6. By binding to XRCC6, LINC-PINT interfered the formation of DNA-PK complex, regulated mitochondria accumulation status and affected the modification of apoptosis proteins, leading to more cell apoptosis. ConclusionOur study provided the first evidence that LINC-PINT promotes cell apoptosis in NPC by binding to XRCC6 and affecting its function.

CCR2+ monocytes/macrophages drive steroid hormone imbalance-related prostatic fibrosis

Benign Prostatic Hyperplasia (BPH) is a complex condition leading to Lower Urinary Tract Symptoms in aging men, characterized by cellular proliferation, smooth muscle dysfunction, inflammation, and fibrosis. While BPH is known to involve heightened macrophage infiltration, the specific contribution of infiltrating monocytes/macrophages to the disease mechanism remains uncertain. This research explores the impact of reducing circulating monocytes and subsequently limiting their tissue infiltration by using Ccr2 knockout (Ccr2-KO) mice. Ccr2-KO and wild type mice were implanted with testosterone and estradiol (T + E2, 25 mg + 2.5 mg) pellets. Urinary function was assessed via weekly void spot assays over 12 weeks, and prostatic macrophage levels were visualized and quantified in tissue sections using an F4/80 antibody. Additionally, Ki-67 staining was used to evaluate cell proliferation, and picrosirius red staining to assess collagen accumulation. Increased voiding frequency which developed in T + E2 mice, was significantly ameliorated in Ccr2-KO mice, however, both Ccr2-KO and wild type (WT) mice showed increased bladder weights after three month, representing a hypertrophic response to bladder outlet obstruction. T + E2 substantially increased the density of macrophages in WT but not Ccr2-KO mouse prostate. Proliferation rate, as indicated by Ki-67 positivity, was elevated in the vental and anterior prostate lobes but was only marginally reduced in Ccr2-KO mice. Most importantly, a significant prostatic collagen accumulation was observed in WT mice that was markedly reduced by Ccr2 deficiency post T + E2 treatment. The absence of Ccr2 mitigates urinary dysfunction and alters prostatic macrophage levels and collagen accumulation in steroid hormone imbalance. These findings suggest a crucial role for monocyte infiltration, giving rise to macrophages or other cell derivatives, to drive fibrosis.

Correlations of high miRNA expressions with traditional proteins and prognosis of breast cancer

Abstract Background In this study, we aimed to analyze the correlations of high expressions of micro ribonucleic acids (miRNAs) with traditional proteins and prognosis of breast cancer. Methods The clinical data of 60 breast cancer patients treated from August 2018 to July 2019 were retrospectively analyzed. All the patients received radical mastectomy combined with postoperative adjuvant chemoradiotherapy and were followed up for 3 years after treatment. The 3-year survival was recorded. The surviving patients were included in a good prognosis group, and the deceased ones were assigned to a poor prognosis group. The levels of miRNAs (miR-182, miR-155, and miR-217) and traditional breast cancer proteins [estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (CerbB-2/HER-2), and cell proliferation factor-67 (Ki-67)] were measured. Receiver operating characteristic (ROC) curve was plotted to investigate the predictive value of miRNA levels for poor prognosis. Results The relative expressions of miR-182, miR-155 and miR-217 were negatively correlated with ER and PR (r&lt;0, P&lt;0.05), but positively correlated with positive Ki-67 expression (r&gt;0, P&lt;0.05). High relative expressions of miR-182, miR-155 and miR-217 and positive Ki-67 expression were risk factors for poor prognosis, and the positive expressions of ER and PR were protective factors (OR&lt;1, P&lt;0.05). The areas under the curves of the relative expressions of miR-182, miR-155 and miR-217 and combined detection for predicting poor prognosis all exceeded 0.70. The combined detection had the highest predictive value. Conclusions The high expressions of miR-182, miR-155 and miR-217 are correlated with the expressions of traditional breast cancer proteins ER, PR, and Ki-67, and may predict the prognosis of breast cancer patients.

Long non-coding RNAs PTENP1, GNG12-AS1, MAGI2-AS3 and MEG3 as tumor suppressors in breast cancer and their associations with clinicopathological parameters.

Breast cancer is the most commonly occurring cancer worldwide and is the main cause of death from cancer in women. Novel biomarkers are highly warranted for this disease. Evaluation of novel long non-coding RNAs biomarkers for breast cancer. The study comprised the analysis of the expression of 71 candidate lncRNAs via screening, six of which (four underexpressed, two overexpressed) were validated and analyzed by qPCR in tumor tissues associated with NST breast carcinomas, compared with the benign samples and with respect to their clinicopathological characteristics. The results indicated the tumor suppressor roles of PTENP1, GNG12-AS1, MEG3 and MAGI2-AS3. Low levels of both PTENP1 and GNG12-AS1 were associated with worsened progression-free and overall survival rates. The reduced expression of GNG12-AS1 was linked to the advanced stage. A higher grade was associated with the lower expression of PTENP1, GNG12-AS1 and MAGI2-AS3. Reduced levels of both MEG3 and PTENP1 were linked to Ki-67 positivity. The NRSN2-AS1 and UCA1 lncRNAs were overexpressed; higher levels of UCA1 were associated with multifocality. The results suggest that the investigated lncRNAs may play important roles in breast cancer and comprise a potential factor that should be further evaluated in clinical studies.

The clinicopathological features and possible physiological mechanisms of only the EGFR-T790M primary mutation in patients with lung adenocarcinoma

BackgroundThe treatment of non-small cell lung cancer (NSCLC) patients can be complicated by the presence of the EGFR-T790M mutation. Although primary or secondary EGFR-T790M mutations have been extensively studied worldwide, there are few reports on the clinicopathological characteristics and physiological mechanisms of lung adenocarcinoma (LUAD) with only the EGFR-T790M primary mutation. MethodsThe clinical data of all LUAD patients with only the EGFR-T790M primary mutation were collected. Immunohistochemical staining was performed on cell cycle-related proteins, targeted therapy indicators, and prognosis-related proteins in the specimens obtained from puncture biopsies or surgeries. ObjectivesThe aim of this study is to analyze the clinicopathological features and possible physiological mechanisms of only the EGFR-T790M primary mutation in LUAD, and to offer recommendations for clinical management. ResultsTwo patients who have only the T790M de novo mutation were both female (2/12,928, 0.02%). β-catenin and Cyclin D1 were both highly expressed. In case 1, IHC results showed a positive Ki67 and mutant P53 and there was a significant increase in serum CYFRA 21–1. Third-generation of EGFR TKIs resulted in a partial response (PR) time of less than 8 months in case 1. In case 2, the patient underwent surgical resection and adjuvant chemotherapy, resulting in a progression-free survival (PFS) time of 25 months. ConclusionThe results suggest that abnormal activation of the Wnt signaling pathway may be specifically associated with the EGFR-T790M primary mutation in LUAD. Furthermore, it has been observed that patients with significant Ki67, mutant P53, and CYFRA 21–1 expression tend to have a poor prognosis.

Abstract PO2-15-12: Novel Transcriptomic Classification System Unveils HER2-Low Breast Tumors

Abstract Breast cancers (BCs) are segregable into subtypes based on their intrinsic molecular features. When evaluating HER2 status, clinicians often rely on IHC, which is plagued by reproducibility issues. The widely used PAM50 transcriptomic system also does not include the HER2-low subtype. Addressing these limitations is particularly important given the recent approval of targeted therapy for HER2-low BCs. Here, we developed a unique transcriptomic classification system that can identify HER2-low BCs. Accurate identification of HER2-low BCs can help physicians navigate treatment selection and, in turn, allow patients to benefit from the new targeted therapy. We analyzed 6,361 BC samples with clinical and pathological annotation, including FISH and IHC data, from three public datasets (TCGA BRCA and SCAN-B [total n = 4,457]; METABRIC [n = 1,904]) for gene expression, differential expression, gene enrichment, copy number alterations, and mutations. An algorithm was applied to categorize samples from TCGA and SCAN-B into subtypes by customizing a gene set, employing UMAP dimensionality reduction, and utilizing clustering with the HDBSCAN algorithm. Each resulting cluster that was associated with a specific gene set was named and excluded from the next analysis. After four iterations, five subtypes were sequentially identified: Basal, HER2-high, HER2-low, Luminal B (LumB), and Luminal A (LumA). The Light GBM-based hierarchical classifier model was trained on the TCGA and SCAN-B cohorts and validated on the METABRIC dataset. Samples with high ERBB2 expression and copy number amplification were classified as HER2-high, and samples with similar PAM50 expression profiles but lacking ERBB2 expression were considered HER2-low. Luminal samples were grouped into two subtypes: LumA, characterized by low proliferation rates, and LumB, characterized by high proliferation rates. HER2-high, Basal, LumA, and LumB subtypes exhibited expected mutational and gene expression profiles. We observed ERBB2 copy number amplification and high gene expression in HER2-high samples from the TCGA and METABRIC cohorts, as confirmed by FISH and IHC in 97% and 93% of samples, respectively. Conversely, we did not see high ERBB2 expression or copy number amplification in the HER2-low samples, which was concordant with an absence of HER2 3+ expression by IHC. HER2-low samples had high mutational frequencies in PTEN, KMT2C, and ERBB2 (12%, 14%, and 8% respectively, adj. p &amp;lt; 0.005, chi-square test). HER2-low samples also showed increased EGFR (logFC = 2.8, adj. p &amp;lt; 0.001) and CLDN8 (logFC = 3.4, adj. p &amp;lt; 0.001) expression levels. The novel classifier identified 55% of the HER2-low samples as the luminal androgen receptor (LAR) Burstein subtype, as a result of higher AR expression than in HER2-high samples (logFC = 2.9, p = 0.04). Classification of SCAN-B luminal samples into the LumA and LumB subtypes also better predicted Ki-67 positivity (≥ 20% of Ki-67+ malignant cells by IHC, F1-score = 0.77) than the previously reported PAM50 classification (F1-score = 0.62). Our refined classifier effectively defined five breast cancer subtypes, including the HER2-low subtype, based on their molecular profiles. By determining HER2 status with transcriptomic data, our classifier may help minimize IHC-related reproducibility issues and, in turn, facilitate more precise treatment decision-making. Given its concordance with copy number amplification, IHC, and FISH data, our classification system can distinguish between HER2-high and HER2-low BCs. Since HER2-low BCs may represent a unique group that requires different treatment approaches, further optimization of our classifier may assist in identifying effective therapies for patients with HER2-low BCs. Citation Format: Polina Turova, Vladimir Kushnarev, Oleg Baranov, Anna Butusova, Sofia Menshikova, Sheila Yong, Anna Love, Konstantin Chernyshov, Nikita Kotlov. Novel Transcriptomic Classification System Unveils HER2-Low Breast Tumors [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-15-12.

Development and Validation of a Prognostic Nomogram for HR+ HER- Breast Cancer.

We aimed to develop a nomogram to predict prognosis of HR+ HER2- breast cancer patients and guide the application of postoperative adjuvant chemotherapy. We identified 310 eligible HR+ HER- breast cancer patients and randomly divided the database into a training group and a validation group. The endpoint was disease free survival (DFS). Concordance index (C-index), area under the curve (AUC) and calibration curves were used to evaluate predictive accuracy and discriminative ability of the nomogram. We also compared the predictive accuracy and discriminative ability of our nomogram with the eighth AJCC staging system using overall data. According to the training group, platelet-to-lymphocyte ratio (PLR), tumor size, positive lymph nodes and Ki-67 index were used to construct the nomogram of DFS. The C-index of DFS was 0.708 (95% CI: 0.623-0.793) in the training group and 0.67 (95% CI: 0.544-0.796) in the validation group. The calibration curves revealed great consistencies in both groups. We have developed and validated a novel and practical nomogram that can provide individual prediction of DFS for patients with HR+ HER- breast cancer. This nomogram may help clinicians in risk consulting and guiding the application of postoperative adjuvant chemotherapy.

Clinical and Imaging Characteristics of Contrast-enhanced Mammography and MRI to Distinguish Microinvasive Carcinoma from Ductal Carcinoma In situ

Rationale and ObjectivesThe prognosis of ductal carcinoma in situ with microinvasion (DCISM) is more similar to that of small invasive ductal carcinoma (IDC) than to pure ductal carcinoma in situ (DCIS). It is particularly important to accurately distinguish between DCISM and DCIS. The present study aims to compare the clinical and imaging characteristics of contrast-enhanced mammography (CEM) and magnetic resonance imaging (MRI) between DCISM and pure DCIS, and to identify predictive factors of microinvasive carcinoma, which may contribute to a comprehensive understanding of DCISM in clinical diagnosis and support surveillance strategies, such as surgery, radiation, and other treatment decisions. Materials and MethodsForty-seven female patients diagnosed with DCIS were included in the study from May 2019 to August 2023. Patients were further divided into two groups based on pathological diagnosis: DCIS and DCISM. Clinical and imaging characteristics of these two groups were analyzed statistically. The independent clinical risk factors were selected using multivariate logistic regression and used to establish the logistic model [Logit(P)]. The diagnostic performance of independent predictors was assessed and compared using receiver operating characteristic (ROC) analysis and DeLong's test. ResultsIn CEM, the maximum cross-sectional area (CSAmax), the percentage signal difference between the enhancing lesion and background in the craniocaudal and mediolateral oblique projection (%RSCC, and %RSMLO) were found to be significantly higher for DCISM compared to DCIS (p = 0.001; p < 0.001; p = 0.008). Additionally, there were noticeable statistical differences in the patterns of enhancement morphological distribution (EMD) and internal enhancement pattern (IEP) between DCIS and DCISM (p = 0.047; p = 0.008). In MRI, only CSAmax (p = 0.012) and IEP (p = 0.020) showed significant statistical differences. The multivariate regression analysis suggested that CSAmax (in CEM or MR) and %RSCC were independent predictors of DCISM (all p < 0.05). The area under the curve (AUC) of CSAmax (CEM), %RSCC (CEM), Logit(P) (CEM), and CSAmax (MR) were 0.764, 0.795, 0.842, and 0.739, respectively. There were no significant differences in DeLong's test for these values (all p > 0.10). DCISM was significantly associated with high nuclear grade, comedo type, high axillary lymph node (ALN) metastasis, and high Ki-67 positivity compared to DCIS (all p < 0.05). ConclusionThe tumor size (CSAmax), enhancement index (%RS), and internal enhancement pattern (IEP) were highly indicative of DCISM. DCISM tends to express more aggressive pathological features, such as high nuclear grade, comedo-type necrosis, ALN metastasis, and Ki-67 overexpression. As with MRI, CEM has the capability to help predict when DCISM is accompanying DCIS.

Genetically engineered mouse model of HPV16 E6-E7 with vaginal-cervical intraepithelial neoplasia and decreased immunity

ObjectiveTo construct models of high-risk human papillomavirus (HPV) infection with precancerous lesions or cervical cancer and explore the immune function. MethodsUsing CRISPR/Cas9, the expression vector HPV16-E6-E7-Rosa26 was microinjected into fertilized eggs of C57BL/6 N mice using homologous recombination, and the F0 generation was obtained for reproduction. Then, the formation of precancerous lesions was promoted via intramuscular injection of estradiol. Presence of precancerous cervical-vaginal intraepithelial lesions, Ki67 and p16 expression levels, and CD8+ T cell proportions in the spleen were evaluated. ResultsTwo F0 generation mice exhibited correct the homologous recombination. Seven positive mice were identified in the F1 generation. After breeding and mating, 25 homozygous and 11 heterozygous HPV16-E6-E7-engineered mice were obtained from the F2 generation. After estradiol benzoate treatment, the cervical-vaginal epithelium appeared as precancerous lesions with positive Ki67 and p16 expression. The percentage of CD8+ T cells decreased. ConclusionHPV16-E6-E7-Rosa26 induced low immune function in mice, and provides a good model for the basic research of the mechanisms of action of HPV infection-associated precancerous lesions or cervical cancer.

P162 Dimethyl fumarate modulates T cell metabolism and function in systemic lupus erythematosus patient samples

Abstract Background/Aims Activated CD4+T cells make a significant contribution to inflammation in systemic lupus erythematosus (SLE) through secretion of proinflammatory cytokines such as IFN-γ and TNF-α. CD4+T cells can also express activating NK receptors such as NKG2D that can engage with stress-induced ligands such as MICA, as noted in lupus nephritis, and mediate nonspecific tissue injury. We know that cellular metabolism regulates the activation of T cells. Evidence from patients with multiple sclerosis indicates that dimethyl fumarate (DMF), an electrophile, targets cellular metabolism to modulate CD4+T cell activation and function. Here, we investigated whether DMF modulates T cell metabolism and function in samples from patients with SLE in a series of in vitro experiments. Methods All experiments were performed using isolated T cells from freshly drawn whole blood samples from patients with SLE. T cells were isolated using negative selection using stem cell or Miltenyei magnetic bead separation kit. Isolated T cells were activated with anti-CD3 and IL-2 and incubated with either DMF at 25μM concentration or DMSO alone for three or seven days at 37 °C and 5% CO2 before harvesting. Results In Seahorse experiments, after three days of incubation, dimethyl fumarate (DMF) inhibited Figure A-i) the oxygen consumption rate (OCR) and A-ii) extra cellular acidification rate (ECAR) in isolated T cells when compared with samples incubated with vehicle, dimethyl sulfoxide (DMSO). Our results revealed that DMF significantly inhibited: 1) aerobic glycolysis and oxidative phosphorylation in activated T cells from patients with SLE (n = 4) (Figure A- i and ii) in vitro; 2) T cell activation and proliferation as assessed by a reduction in the frequency of CD69 (n = 4) and D) Ki67 (n = 2) positivity, respectively (Figure B-E); 3) Collectively, these results suggest that DMF inhibits T cell activation and proliferation in samples from patients with SLE. After 7 days of incubation, DMF significantly inhibited the expression of activating NK receptors CD158a and NKG2D on T cells whereas there was a trend toward enhancing the expression of inhibitory NK receptors NKG2A and CD158b (Figure F-I). After 7 days of incubation, DMF significantly reduced intracellular expression of IFN-γ, TNF-α, IL-17 and secretion of pro-inflammatory cytokines IFN-γ and TNF-α in supernatants (Figure J - N). Conclusion Our preliminary data indicated that, in SLE patient samples, DMF modulates metabolic programming of CD4+ T cells and inhibits glycolysis and oxidative phosphorylation of activated CD4+ T cells. In vitro, DMF inhibited: T cell activation; proliferation; the expression of activating NK receptors; and secretion of proinflammatory cytokines from T cells patients with SLE. Taken together with the existing safety data in humans, these data provide mechanistic rationale for investigating the potential of dimethyl fumarate, with a distinct mechanism of action, as a novel therapy for SLE. Disclosure L. Kell: None. K. Shah: None. S. Taylor: None. R. De Maeyer: None. D.A. Isenberg: None. D. Sen: None. M. Castelino: None. M. Leandro: None. A. Akbar: None. V. Reddy: Grants/research support; UCLH Biomedical research centre funded this work, Dr.Reddy's work was supported through MR/T024968/1 MRC-CARP Fellowship.

Predicting abiraterone efficacy in advanced prostate cancer: Insights from marker of proliferation Ki67.

KI67 is a well-known biomarker reflecting cell proliferation. We aim to elucidate the predictive role of KI67 in the efficacy of abiraterone for patients with advanced prostate cancer (PCa). Clinicopathological data of 152 men with metastatic PCa, who received abiraterone therapy were retrospectively collected. The KI67 positivity was examined by immunohistochemistry using the prostate biopsy specimen. The predictive value of KI67 on the therapeutic efficacy of abiraterone was explored using Kaplan-Meier curve and Cox regression analysis. The endpoints included prostate-specific antigen (PSA) progression-free survival (PSA-PFS), radiographic PFS (rPFS), and overall survival (OS). In total, 85/152 (55.9%) and 67/152 (44.1%) cases, respectively, received abiraterone at metastatic hormone-sensitive (mHSPC) and castration-resistant PCa (mCRPC) stage. The median KI67 positivity was 20% (interquartile range: 10%-30%). Overall, KI67 rate was not correlated with PSA response. Notably, an elevated KI67-positive rate strongly correlated with unfavorable abiraterone efficacy, with KI67 ≥ 30% and KI67 ≥ 20% identified as the optimal cutoffs for prognosis differentiation in mHSPC (median PSA-PFS: 11.43 Mo vs. 26.43 Mo, p < 0.001; median rPFS: 16.63 Mo vs. 31.90 Mo, p = 0.003; median OS: 21.77 Mo vs. not reach, p = 0.005) and mCRPC (median PSA-PFS: 7.17 Mo vs. 12.20 Mo, p = 0.029; median rPFS: 11.67 Mo vs. 16.47 Mo, p = 0.012; median OS: 21.67 Mo vs. not reach, p = 0.073) patients, respectively. Multivariate analysis supported the independent predictive value of KI67 on abiraterone efficacy. In subgroup analysis, an elevated KI67 expression was consistently associated with unfavorable outcomes in the majority of subgroups. Furthermore, data from another cohort of 79 PCa patients with RNA information showed that those with KI67 RNA levels above the median had a significantly shorter OS than those below the median (17.71 vs. 30.72 Mo, p = 0.035). This study highlights KI67 positivity in prostate biopsy as a strong predictor of abiraterone efficacy in advanced PCa. These insights will assist clinicians in anticipating clinical outcomes and refining treatment decisions for PCa patients.

Abstract 4255: A systematic framework for efficient generation of expandable patient-derived 3D sarcoma models

Abstract Introduction: Sarcomas are rare connective tissue tumors with over 100 described subtypes. High heterogeneity within and among sarcoma sub-entities and low incidence contribute to poor therapeutic success. Patient-derived 3D models (PDMs), i.e. organoids and spheroids, closely recapitulate features of the original tumor, e.g. cell-to-cell interaction, differentiation potential and heterogeneity. However, PDMs are rarely available or even lacking for most sarcoma sub-entities, constituting a major hurdle for sarcoma precision oncology and research. Here, we present a highly efficient and systematic framework to generate long-term 3D models for distinct sarcoma subtypes, which we developed within the HEROES-AYA consortium. Methods: Tumors were received directly after surgery and processed within 24 hours. After enzymatic dissociation, cell clumps were seeded in 384-well plates with and without Matrigel. Each tumor was cultivated on an array of 140 distinct culture conditions, differing in contribution and concentration of pathway inhibitors and activators. Organoid and spheroid growth was assessed over time via imaging and AI-based algorithms to identify best-growing conditions. Results: Initially, we combined Ewing sarcoma (EwS) secreted factors and potentially relevant cytokines to generate a matrix of 140 diverse media, named Media Test Plate (MTP). The MTP was tested on five EwS tumors, allowing the identification of optimal culture conditions with 100% efficiency. When transplanted in NSG mice, the established PDMs showed tumorigenicity potential and Ewing sarcoma-specific CD99 marker expression. The MTP was then tested on four synovial sarcomas (SyS) and five myxoid liposarcomas with a 75% and 50% success rate, respectively. The optimal media, as identified by MTP, allowed the cultivation of one EwS and one SyS out of two, respectively, even with limited cell count. Additional PDMs generated include one undifferentiated, one alveolar soft tissue and one spindle cell sarcoma. Established cultures were characterized by Ki67 positivity, ranging from 40% to 70%, and expression of sarcoma subtype-specific markers. EwS models resulted 100% CD99 positive, while TLE1 positivity in SyS models was ≈90%. DNA and RNA sequencing of PDMs will show whether they resemble the genetic and transcriptional features of the original tumors. Conclusions: We here present a novel systematic protocol to generate organoids and spheroids from different sarcoma subtypes. To date, no such systematic protocol is available for sarcoma models generation. Our success rate is comparable to the one of intestinal and pancreatic organoids and exceeds those of 2D and PDX sarcoma cultures, which is ≈20%. Current work aims to adapt the MTP to a broad range of sarcoma subtypes, including rare entities. The efficient generation of expandable PDMs from a wide range of sarcomas will further fuel basic and translational research. Citation Format: Claudia Dagostino, Waqar Hussain, Jasmina Paluncic, Marcelo Zoccoler, Jessica Pablik, Daniela Richter, Lisanne Knol, Ana Banito, Johanna Wagner, Ivona Mateska, Daniel E. Stange, Ina Oehme, Stephan Richter, Stefan M. Pfister, Stefan Fröhling, Claudia Scholl, Jürgen Weitz, Klaus-Dieter Schaser, Christoph Heining, Hanno Glimm, Claudia R. Ball. A systematic framework for efficient generation of expandable patient-derived 3D sarcoma models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4255.