Min Ji Research Articles

South Korean Capital Market Reacts to Park Ji Min's Solo Debut

South Korean Capital Market Reacts to Park Ji Min's Solo Debut

Abstract PO1-23-05: Exploratory clinical trial of preoperative non-invasive localization before surgery in breast cancer patients using augmented reality technology

Abstract Purpose: A single-center, randomized, prospective exploratory clinical trial to assess the clinical efficacy of augmented reality(AR)-based breast cancer localization medical imaging solution in patients with breast cancer Methods: This prospective exploratory clinical trial enrolled 20 women who were diagnosed with invasive breast cancer between the ages of 19 and 70, had a single lesion or multifocal lesion with a lesion size of 5mm or more and 30mm or less, had no metastasis to other organs, and had not received prior chemotherapy. All patients underwent mammography, ultrasound, CT, and MRI for preoperative assessment. Patients were randomly assigned to US-guided skin marking (control) and SKIA-breast (AR localization) groups of 10 each. Result: Two surgeons performed breast-conserving surgery on twenty patients. Pathologic evaluation of all patients confirmed negative margins. Two independent pathologists evaluated marginal distance, and neither the two reader's estimates (R1, 6.20±4.37 vs. 5.04±3.47, p=0.519; R2, 5.10±4.31 vs. 4.10±2.38, p= 0.970) nor the two reader's average values (5.65±4.19 vs. 4.57±2.84, p= 0.509) showed any difference between the two groups. In comparing the tumor plane area ratio, there was no statistically significant difference between the two groups for the two readers (R1, 15.90±9.52 vs. 19.38±14.05, p=0.525; R2, 15.32±9.48 vs. 20.83±12.85, p=0.290) and the two reader's mean values (15.56±9.11 vs. 20.09±13.38, p=0.388). Based on the two surgeons' responses, convenience, safety, satisfaction, and reusability were all superior in the AR localization group (p=0.000). Conclusion: AR localization is an acceptable alternative to US-guided skin marking with no significant differences in surgical outcomes. Citation Format: Minah Lee, Jun Woo Lee, Woosung Lim, Joohyun Woo, Hyun-Goo Kim, Se Hyun Paek, SangHui Park, Ji Min Kim, Jin Chung, Jee Eun Lee, Jeoung Hyun Kim. Exploratory clinical trial of preoperative non-invasive localization before surgery in breast cancer patients using augmented reality technology [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 PO1-23-05.

Abstract PO4-03-05: Prognostic value of Ki67 expression in post-treatment tumors of patients with residual triple-negative breast cancer after neoadjuvant chemotherapy

Abstract Introduction Patients with triple-negative breast cancer (TNBC) who do not achieve pathological complete response (pCR) against neoadjuvant chemotherapy (NAC) have a poor prognosis. The prognosis of these patients can be differentiated using various parameters, including the Residual Cancer Burden (RCB) index and tumor-infiltrating lymphocytes. In this study, we took a different angle and aimed to evaluate the prognostic value of post-treatment Ki67 expression, which was examined in tumors following NAC in patients with non-pCR TNBC. Methods A retrospective review of clinical records from February 2008 to December 2021 was conducted of patients from Gangnam Severance Hospital and Asan Medical Center, both in Seoul, South Korea. We included patients with non-metastatic TNBC who underwent NAC including anthracycline and taxane regimens, followed by curative surgery, regardless of adjuvant capecitabine receipt. Ki67 expression and the RCB index were evaluated using residual tumors obtained from surgery. High Ki67 expression was defined as ≥20%. The 5-year recurrence-free survival (RFS) was estimated using Kaplan-Meier analysis, and hazard ratios (HR) were calculated using Cox regression analysis. Results This study included 338 patients with available Ki67 expression data in residual tumors. Among them, 110 patients (30.9%) had low Ki67 expression, while 228 patients (64%) had high Ki67 expression. At a median follow-up of 34 months, those with low Ki67 expression had a 5-year RFS rate of 82.6%, while those with high Ki67 expression had a rate of 58.3%, with a HR of 0.345 (95% CI 0.210-0.565, p< 0.001). When stratified by the RCB index, the 5-year RFS of RCB-I patients was 93%, RCB-II patients 70.2%, and RCB-III patients 40.5%. When assessing survival outcomes based on both Ki67 expression and the RCB index, patients with RCB-I and low Ki67 (n=26) had a 100% 5-year RFS rate. Patients with RCB-I and high Ki67 (n=24) had a rate of 83.3%. Notably, in patients with RCB-III and high Ki67 (n=62), the 5-year RFS rate was 35.5% and there was no significant difference in RFS based on the receipt of adjuvant capecitabine (median RFS: capecitabine - 18 months, observation - 15 months, p-value=0.994). Conclusions Our findings demonstrate the prognostic value of Ki67 expression in residual TNBC after NAC, indicating that cases with low Ki67 expression have a favorable outcome. Combining Ki67 expression with the RCB index allows identification of patients with good residual disease (i.e. low Ki67 expression and RCB-I) who could be potential candidates for de-escalating adjuvant treatments such as capecitabine or pembrolizumab. However, for patients with high Ki67 expression and RCB-III, novel strategies are required to improve survival outcomes beyond the use of capecitabine. Citation Format: Yoonwon Kook, Soo-Young Lee, Seung Ho Baek, Min Ji Kim, Junghyun Kim, Sohyun Moon, Seung Eun Lee, Soong June Bae, Joon Jeong, Sae Byul Lee, Sung Gwe Ahn. Prognostic value of Ki67 expression in post-treatment tumors of patients with residual triple-negative breast cancer after neoadjuvant chemotherapy [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 PO4-03-05.

Abstract PS16-06: Tumor-infiltrating lymphocytes and pathologic response to neoadjuvant chemotherapy with the addition of platinum and pembrolizumab in TNBC: A single-center real-world study

Abstract Background Previous studies have presented compelling evidence suggesting that the inclusion of platinum agents alongside anthracyclines and taxanes could potentially enhance treatment outcomes in high-risk triple-negative breast cancer (TNBC). Moreover, pembrolizumab has been integrated into clinical practice as a part of standard-of-care for non-metastatic TNBC with high risk. In light of these findings, we undertook a real-world study to investigate the impact of incorporating platinum agents and pembrolizumab on achieving pathologic complete response (pCR) in TNBC patients undergoing neoadjuvant chemotherapy (NAC). Furthermore, we specifically examined the influence of tumor-infiltrating lymphocytes (TILs) on the treatment outcomes. Patients and Methods In this real-world study conducted at Gangnam Severance Hospital, Seoul, Republic of Korea, we analyzed a cohort of 398 patients with TNBC who underwent surgery following NAC between March 2007 and November 2022. Among them, 247 patients received an anthracycline-taxanes (A-T), 120 received a carboplatin regimen including A-T, and 31 received a pembrolizumab regimen including A-T-carboplatin as part of their neoadjuvant chemotherapy treatment. TIL was evaluated in biopsied samples prior to NAC according to the guideline of TIL international working group. The high TIL was defined with a cutoff of 50%. Results Among the 398 patients analyzed, 87 (21.9%) had high TIL tumors. The pCR rates were 32% in the anthracycline-taxane (A-T) regimen group, 57% in the A-T-carboplatin regimen group, and 68% in the pembrolizumab with A-T-carboplatin regimen group. Within the high TIL group, the pCR rate did not increase with the addition of carboplatin (51.8% in the A-T group and 41.7% in the A-T-carboplatin group), but reached 85.7% with the addition of pembrolizumab and carboplatin. Among the low TIL group, the pCR rate increased from 26.7% to 61.1% with the addition of carboplatin, but there was no difference in the pCR rate between the carboplatin and pembrolizumab groups (61.1% and 60.9%, respectively). In clinically node-positive patients, the pCR rate significantly increased with pembrolizumab in the high TIL group (40.9% versus 100%, p=0.035). However, in low TIL patients, the addition of carboplatin alone significantly increased the pCR rate to 62.3%, whereas the addition of pembrolizumab did not show the same effect. Conclusions Our real-world data consistently demonstrates an increased pCR rate with the addition of carboplatin and pembrolizumab. Among patients with high TIL, the addition of carboplatin did not result in an elevated pCR rate. However, the addition of pembrolizumab tended to maximize the pCR rate, surpassing 80%. On the other hand, among patients with low TIL, the addition of carboplatin significantly increased the pCR rate, while the addition of pembrolizumab did not have the same effect. Efforts should be made to improve the response to pembrolizumab-containing regimens for patients with low baseline TIL levels. Citation Format: Min Ji Kim, Yoonwon Kook, Seung Ho Baek, Junghyun Kim, Sohyun Moon, Seung Eun Lee, Jee Hung Kim, Soong June Bae, Sung Gwe Ahn, Joon Jeong. Tumor-infiltrating lymphocytes and pathologic response to neoadjuvant chemotherapy with the addition of platinum and pembrolizumab in TNBC: A single-center real-world study [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 PS16-06.

Abstract PO2-08-05: ERBB2 mutated breast cancer detected by next generation sequencing: integrated analysis based on real-world data and The Cancer Genome Atlas

Abstract Background ERBB2 mutation has been recognized as an actionable target for pan-HER tyrosine kinase inhibitors in the era of precision medicine for solid tumors. In our real-world cohort utilizing next-generation sequencing (NGS), we successfully identified cases of ERBB2-mutated breast cancer. Furthermore, we investigated the clinical and pathological characteristics of these cases by integrating our data with The Cancer Genome Atlas (TCGA). Methods Our real-world cohort with NGS included 423 breast cancer patients treated at Gangnam Severance Hospital in Seoul, Republic of Korea, between April 2017 and January 2023. Among these patients, 13 were confirmed to have ERBB2 mutation through NGS analysis. We also incorporated data from TCGA database, which included 818 cases with ERBB2 sequencing. We compared the clinical characteristics (age, sex, stage, and ER, PR, and HER2 status) between the two groups. Furthermore, we examined the frequency of two of the most common mutations, PIK3CA and TP53, in both groups. Additionally, we investigated the distribution of PAM50 subtypes in the TCGA cohort. Results This study analyzed a total of 1,244 cases with NGS data. Among these cases, 31 (2.5%) exhibited ERBB2 mutation, with 13 patients identified in our dataset and 18 in the TCGA data. Among the 31 cases with ERBB2 mutation, 21 (67.7%) had HER2-negative disease. No significant differences were observed in other clinical characteristics based on ERBB2 status. Within the group of 31 ERBB2-mutated cases, TP53 mutations were found in 12 cases (38.7%), while PIK3CA mutations were found in 12 cases (38.7%). In the TCGA dataset, 4 cases (22.2%) with ERBB2 mutation were classified as HER2-E subtype, and the rate of HER2-E subtype was significantly higher in the ERBB2-mutated group compared to the ERBB2-wild group (22.2% vs. 7.6%, p=0.024). Conversely, 14 cases (77.8%) with ERBB2 mutation exhibited a non-HER2 enriched subtype. Conclusions Consistent with previous knowledge, ERBB2 mutations can be detected in HER2-negative breast cancer, despite their rarity. Furthermore, a considerable proportion of ERBB2-mutated breast cancer may depend on various oncogenic signaling pathways other than the HER2 pathway. Further studies are warranted to optimize therapeutic strategies for ERBB2-mutated breast cancer. Citation Format: Junghyun Kim, Yoonwon Kook, Seung Ho Baek, Min Ji Kim, Sohyun Moon, Seung Eun Lee, Jee Hung Kim, Soong June Bae, Joon Jeong, Sung Gwe Ahn. ERBB2 mutated breast cancer detected by next generation sequencing: integrated analysis based on real-world data and The Cancer Genome Atlas [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 PO2-08-05.

Abstract PO3-23-05: Capsular contracture after post-mastectomy radiotherapy in the patients undergoing implant-based breast reconstruction: impact of implant positioning and two-stage surgery

Abstract Background Capsular contracture is a significant concern in patients undergoing post-mastectomy radiotherapy (PMRT) following implant-based breast reconstruction. It negatively impacts cosmetic outcomes and can have a profound effect on the individual's quality of life. Our study aimed to explore whether the degree of capsular contracture varies based on the placement of the inserted implant and the type of operation (one- or two-staged). Patients and Methods This retrospective study was conducted at a single center, Ganganm Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea. Our study included patients who underwent PMRT following total mastectomy and implant-based breast reconstruction surgery between January 2017 and September 2022. To assess the degree of capsular contracture, we evaluated the presence of capsular contracture, particularly severe capsular contracture classified as Baker grade 3 or higher, as well as implant migration. The implants were placed either in the pre-or sub-pectoral position, and the surgical approach employed was either direct-to-implant (DTI) or two-staged operation. Results A total of 195 patients were included in the study, with 83 (42.6%) patients in the pre-pectoral group and 112 (57.4%) patients in the sub-pectoral group. In addition, 116 underwent a two-stage operation, while 79 underwent DTI surgery. There was a significant difference in the occurrence of capsular contracture based on the implant placement, with 16 patients (19.3%) in the pre-pectoral group and 46 patients (41.1%) in the sub-pectoral group experiencing this complication (OR 4.142 [1.973-8.698]). Furthermore, the severity of capsular contracture differed significantly between the two groups, with 5 patients (6.0%) in the pre-pectoral group and 16 patients (14.3%) in the sub-pectoral group affected (OR 3.434 [1.153-10.227]). The incidence of capsular contracture was lower in the two-stage operation group compared to the DTI group (28 [23.9%] vs 34 [38.6%]; OR 3.064 [1.528-6.141]), and the severity of capsular contracture was also reduced (9 [7.7%] vs 12 [14.5%]; OR 2.854 [1.092-7.455]). There were no significant differences in other complications such as seroma and infection. In addition, sub-pectoral placement was identified as a significant risk factor for implant upward migration (OR 2.531 [95% CI, 1.263-5.071]). Conclusions Our findings suggest that pre-pectoral reconstruction and the two-stage operation are beneficial for patients who may undergo PMRT based on their initial nodal stage. These approaches can help reduce the incidence of capsular contracture and abnormal implant migration following radiation, leading to improved aesthetic outcomes and greater patient satisfaction. Citation Format: Sohyun Moon, Kyunghyun Min, Jung Hwan Eom, Yoonwon Kook, Seung Ho Baek, Junghyun Kim, Min Ji Kim, Seung Eun Lee, In Sik Yun, Tai Suk Roh, Soong June Bae, Joon Jeong, Young Seok Kim, Sung Gwe Ahn. Capsular contracture after post-mastectomy radiotherapy in the patients undergoing implant-based breast reconstruction: impact of implant positioning and two-stage surgery [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 PO3-23-05.

Abstract PO3-07-06: Correlation between residual microcalcification and in-breast pathologic response in relation to MRI response and the subtypes after neoadjuvant chemotherapy

Abstract Background The significance of residual microcalcifications after neoadjuvant chemotherapy (NAC) in determining the extent of surgical intervention in breast cancer remains unclear. This study aimed to assess whether residual microcalcifications after NAC correlate with the residual disease in patients with breast cancer stratified by subtypes, particularly in excellent radiologic responders. Methods We conducted a retrospective study of patients with breast cancer who underwent NAC followed by curative surgery between January 2007 and December 2022. We evaluated the presence of suspicious microcalcifications on pre-NAC mammography and residual microcalcifications on post-NAC mammography. In the patients who had residual microcalcifications on post-NAC mammography, the rates of breast pathologic complete response (pCR), defined as the absence of invasive cancer (ypT0/is) or complete breast pCR defined as the absence of invasive cancer and in-situ cancer in the breast (ypT0), was assessed according to the MRI response and subtypes. We defined complete MRI response as the resolution of suspicious enhancement in the breast and axilla after NAC. Results Of the 1078 patients, 554 (51.4%) had suspicious microcalcifications at baseline, of which 518 (93.5%) had residual microcalcifications after NAC. Among the 518 patients with residual microcalcifications, 93 (18.0%) achieved a complete MRI response. We observed a difference in breast pCR rates depending on MRI response and hormone-receptor (HR) status. In the patients without complete MRI response, about one-third of patients (139 of 425 [32.7%]) achieved a breast pCR, irrespective of HR status (19.3% [47 of 244] in HR-positive breast cancer and 50.8% [92 of 181] in HR- negative breast cancer). Of the 93 patients who achieved a complete MRI response, the breast pCR rates were 64.3% (27 of 42) in HR-positive breast cancer and 96.1% (49 of 51) in HR-negative breast cancer, respectively. Moreover, the breast complete pCR rate was 54.8% (23 of 51) in HR-positive breast cancer and 88.2% (45 of 51) in HR-negative breast cancer, including 87.2% (34 of 39) in HR-HER2+ breast cancer and 91.7% (11 of 12) in triple-negative breast cancer. Conclusion Our results suggest that the clinical relevance of the residual microcalcifications differs according to the breast cancer subtypes. For patients with HR-positive breast cancer, removal of the residual microcalcifications should be considered to ensure complete cancer removal, regardless of MRI response. In contrast, de-escalating surgery may be considered in patients with HR-negative breast cancer who achieve complete MRI response after NAC. Citation Format: Soong June Bae, Seung Ho Baek, Seung Eun Lee, Min Ji Kim, Sohyun Moon, Junghyun Kim, Yoonwon Kook, Joon Jeong, Sung Gwe Ahn. Correlation between residual microcalcification and in-breast pathologic response in relation to MRI response and the subtypes after neoadjuvant chemotherapy [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 PO3-07-06.

Abstract 4242: Preserving lung cancer patient mutations in 3D organoid models: Advancing cancer research through innovative culture systems

Abstract Lung cancer is one of the most prevalent cancers worldwide. There are currently many anticancer drugs available, but they have numerous issues in terms of treatment, such as drug resistance and recurrence. Culturing systems that can replace a patient's cancer tissue are crucial, and the existing 2D culturing systems have many limitations. Patient-derived cancer organoid culture is the most advanced culture system for understanding mechanism of cancers. Using a 3D organoid culture system, we have successfully established a culture system for lung cancer using biopsy/surgical specimens and malignant effusions, including a long-term culture system. There are two critical indicators to determine the success of 3D organoid culture. One is whether the organoids retain their cancer-specific mutations from patient’s lung cancer tissue, and the second is whether the organoids grow well and can be maintained in long-term culture for more than 20-30 passages. We typically assess gene mutations in EGFR, ALK, ROS, and P53 when evaluating lung cancer organoids. We confirm these mutations when we establish organoids. and currently we have established a total of 127 patient-derived lung cancer organoids. Among the 127 organoids, we completed NGS analysis on 108 of them and validated that 86.5% exhibit similarity when compared to lung cancer tissues. Additionally, we achieved a 100% retention of mutations in the long-term culturing of these organoids. Our studies indicate that patient-derived lung cancer organoids represent a meaningful organoid system for cancer tissue replacement and treatment response in the context of precision cancer medicine. Citation Format: Ji-yeon Park, Seo Rin Gu, Jiyeon Lee, Na-Gyeong Lee, Dojin Choi, Sang Eun Park, Ji Min Kim, Jinguen Rheey. Preserving lung cancer patient mutations in 3D organoid models: Advancing cancer research through innovative culture systems [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 4242.

Abstract 1037: Clinical application of next-generation digital PCR capable of real-time analysis to HER2 measurement as a novel diagnostic in breast cancer: A multicenter retrospective study

Abstract HER2 testing is still challenging due to the subjective natures of immunohistochemistry (IHC) and in situ hybridization (ISH), standard methods for determining HER2 status. Here, we developed a clinically reliable HER2 testing method enabling ultra-fast detection of HER2 gene amplification with high accuracy by using the digital real-time PCR (drPCR) system. To test the clinical validity and standardize procedures of drPCR-based HER2 status evaluation, three independent breast cancer cohorts from different institutions were enrolled, which assigned as a training (SCHU hospital, n = 103) and two validation sets (SNU hospital, n = 170; CNUH hospital, n = 45), and the drPCR assay was compared with current standard HER2 testing methods. In the training cohort, the HER2/CEP17 ratio values from FISH and drPCR tests were highly correlated (r2 = 0.81; P < 0.001), and the drPCR results displayed 98.1% concordance to HER2 status defined by IHC and/or FISH with 92.6% sensitivity and 100% specificity. Eight samples further verified by targeted NGS showed 100% concordance of dPCR to NGS. Consistently, two validation cohorts also showed high concordance of drPCR to IHC and/or ISH results (accuracy = 97.1% and 97.8% in SNU and CNUH cohorts, respectively). The optimal cutoff for HER2 positivity in the drPCR assay was set as a HER2/CEP17 ratio ≥ 1.9 with AUC of 0.963 based on the results from training cohort, and the same cut-off for drPCR was applicable to two independent validation cohorts, supporting the clinical validity of our drPCR-based HER2 assessment. In some discordant cases, low tumor purity (≤ 25%) was observed and microdissection partly improved the drPCR results. The discordance between drPCR and ISH results was also found in marginal HER2+ cases with HER2/CEP17 ratio 2-3, but these cases showed inter-observer variability when re-evaluating the ISH/IHC data due to intratumoral HER2 heterogeneity. Of note, in HER2 IHC3+ cases with negative drPCR results, re-evaluation of IHC using an artificial intelligence (AI)-based HER2 scoring system revised the HER2 IHC 3+ score to 2+, and ISH assessment also confirmed that these cases are indeed HER2-negative, proving the high accuracy of HER2 CN drPCR assay. In conclusion, given the advantages of drPCR-based HER2 assessment with high accuracy, sensitivity, and simplicity, the drPCR assay could be a complementary or alternative method to IHC and ISH to greatly improve current HER2 testing. Citation Format: Hayeon Kim, Soo Young Park, Sohyeon Yang, Min Ji Song, Da Sol Kim, Jin hyuk Chang, YoonSik Kim, Hee-Joo Choi, Nam Hun Heo, Hee-Young Won, Ji-Hye Park, Minsik Song, Seung-Shick Shin, Do Young Lee, Si-Hyong Jang, Jeong-Yeon Lee, Han Suk Ryu. Clinical application of next-generation digital PCR capable of real-time analysis to HER2 measurement as a novel diagnostic in breast cancer: A multicenter retrospective study [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 1037.

Abstract 6993: SLC1A4 is associated with metabolic reprogramming in triple-negative breast cancer

Abstract The solute carrier protein (SLC) family is transporters as integral membrane proteins that transport solutes in an ATP-independent manner. The SLC1 family consists of five high-affinity glutamate transporters and two neutral amino acid transporters, among which SLC1A4 transports the neutral amino acids and is known to participate in various biological processes, including metabolism and tumorigenesis. However, the relationship between SLC1A4 and breast cancer remains unclear. Here, we aimed to verify the role of SLC1A4 in triple-negative breast cancer (TNBC). To reveal the characteristics of SLC1A4 in TNBC cell lines, five cell lines (HCC38/OE, HCC1395/OE, HCC1937/OE, MDA-MB-468/KD, and Hs578T/KD) that regulate gene expression of SLC1A4 were established using a lentiviral system. The two major energy-producing pathways, glycolysis and oxidative phosphorylation, were measured according to SLC1A4 gene expression. In addition, cell proliferation, cell migration, and cell invasion ability were confirmed upon overexpression or knock-down of SLC1A4. To confirm cancer stem cell function according to SLC1A4 gene expression, ALDH activity and sphere formation ability were evaluated. To ensure transcript changes due to SLC1A4 expression, RNA sequencing was performed. Anti-cancer drug (cisplatin, carboplatin, paclitaxel, and doxorubicin) sensitivity was also tested. The result showed that energy production efficiency was significantly reduced in cells where SLC1A4 expression was suppressed. In addition, in cells overexpressing the SLC1A4 gene, the presence of SLC1A4 was confirmed to increase cell proliferation, migration, and invasion ability significantly. Transcriptome analysis results showed notable changes in genes related to signaling receptor binding. Regarding material transport, to investigate whether there was a change in amino acid uptake ability according to SLC1A4 gene expression, no difference was observed. In the drug responses, doxorubicin showed a significant sensitive response in the absence of SLC1A4 gene expression. Taken together, SLC1A4 is a potential oncogene that not only induces rapid proliferation, aggressive invasion, and migration through metabolic reprogramming but also contributes to increasing cancer stem cell capabilities. In addition, it shows the sensitive response to ADR when SLC1A4 is low or absent, so it can be used as a treatment strategy for TNBC. Citation Format: Soo Young Park, Da Sol Kim, Hayeon Kim, Min Ji Song, Han Suk Ryu. SLC1A4 is associated with metabolic reprogramming in triple-negative breast cancer [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 6993.

Abstract 6990: RHBDF1 is a potential modulator of EGFR activation and oncogenic biomarker in triple-negative breast cancer

Abstract Recently, our proteomics study on breast cancer (BC) reported a possible association of RHBDF1 with triple-negative breast cancer (TNBC). The overall survival of TNBC patients on METABRIC data set implicated that the RHBDF1 high-expression group has a shorter life expectancy than the RHBDF1 low-expression group. Although many TNBC patients have high expression levels of RHBDF1 and poor prognosis, the mechanism of RHBDF1 in the pathogenesis of TNBC remained unclear. Rhomboid 5 homolog 1 (RHBDF1) is a catalytically inactive pseudoprotease on the Golgi and endoplasmic reticulum membrane. Despite its inactive status of peptidase, it regulates the activity of ADAM17 protease that cleaves the extracellular portion of EGFR ligands such as TGF alpha and EGF. Eventually, RHBDF1 and ADAM17 complex activate the EGFR signaling pathway, thereby increasing cell proliferation, migration, and tumorigenesis. First of all, we recruited the clinical data of the overall survival (OS) and disease-free survival (DFS) in the hospital of Seoul National University (SNUH cohort, n= 203) and compared IHC score 0 or 1 with survival rate. To investigate the underlying biological mechanism of RHBDF1 in TNBC, the effect of knockdown or overexpression of RHBDF1 was observed in TNBC cell lines (MDA-MB-468, HCC1143 and BT20) using siRNA (small interfering RNA) and lentiviral systems. Cell proliferation assay was performed to clarify whether RHBDF1 affects cell growth. Then, we estimated the ability of migration, invasion, and sphere formation to confirm the characteristics of cancer cells including cancer stemness and metastasis. SNUH cohort with TNBC patients showed that the RHBDF1 high-expression group has a poorer disease-free survival (DFS) than the low-expression group (p<0.05). In vitro assay, RHBDF1 knockdown inhibited proliferation in MDA-MB-468 and HCC1143. RHBDF1 downregulation also decreased the ability of migration and invasion. We found that RHBDF1 activates specific cell growth signaling pathways and increases cell mobility in TNBC. The sphere formation assay was performed to measure cancer stemness characteristics. As a result, RHBDF1 knockdown TNBC cell lines couldn’t form spheres relative to RHBDF1 overexpressed TNBC cell lines. In conclusion, we demonstrated that RHBDF1, a potential triple-negative breast cancer biomarker, is highly amplified in TNBC patients and TNBC cell lines. Its functions of accelerating cell proliferation, metastasis and cancer stemness were unveiled. But we need to study ultimately how RHBDF1 regulates ADAM17 activity at Golgi and endoplasmic reticulum membrane and which transcription factor activates RHBDF1 expression. Citation Format: Hayeon Kim, Soo Young Park, Da Sol Kim, Cheng Hyun Lee, Min Ji Song, Han Suk Ryu. RHBDF1 is a potential modulator of EGFR activation and oncogenic biomarker in triple-negative breast cancer [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 6990.

Abstract A005: Ultra-rapid and precise measurement of HER2 copy number alteration by next-generation digital PCR capable of real-time analysis in patients with breast cancer: A multicenter retrospective study

Abstract The HER2 diagnostics is necessary for selection of patients harboring HER2 gene amplification or protein overexpression who will benefit from anti-HER2 therapies in breast cancer. However, HER2 testing is still challenging due to the subjective natures of immunohistochemistry (IHC) and in situ hybridization (ISH), standard methods for determining HER2 status. Thus, a new method is needed to accurately quantify HER2 levels. Here, we developed a clinically reliable HER2 testing method enabling ultra-fast detection of HER2 gene amplification with high accuracy by using the digital real-time PCR (drPCR) system, a potential new diagnostic platform with improved performance by integrating both real-time and digital PCR technologies. For drPCR-based HER2 copy number (CN) measurement, primer-probe sets specific to HER2 gene and a genomic region adjacent to chromosome 17 centromere (CEP17) were designed, and the optimal drPCR condition was determined in clinical breast tumor specimens. To test the clinical validity and standardize procedures of drPCR-based HER2 status evaluation, three independent breast cancer cohorts from different institutions were enrolled, which assigned as a training (SCHU hospital, n = 103) and two validation sets (SNU hospital, n = 170; CNUH hospital, n = 45), and the drPCR assay was compared with current standard HER2 testing methods. In the training cohort, the HER2/CEP17 ratio values from FISH and drPCR tests were highly correlated (r2 = 0.81; P < 0.001), and the drPCR results displayed 98.1% concordance to HER2 status defined by IHC and/or FISH with 92.6% sensitivity and 100% specificity. Eight samples further verified by targeted NGS showed 100% concordance of dPCR to NGS. Consistently, two validation cohorts also showed high concordance of drPCR to IHC and/or ISH results (accuracy = 97.1% and 97.8% in SNU and CNUH cohorts, respectively). The optimal cutoff for HER2 positivity in the drPCR assay was set as a HER2/CEP17 ratio ≥ 1.9 with AUC of 0.963 based on the results from training cohort, and the same cut-off for drPCR was applicable to two independent validation cohorts, supporting the clinical validity of our drPCR-based HER2 assessment. In some discordant cases, low tumor purity (≤ 25%) was observed and microdissection partly improved the drPCR results. The discordance between drPCR and ISH results was also found in marginal HER2+ cases with HER2/CEP17 ratio 2-3, but these cases showed inter-observer variability when re-evaluating the ISH/IHC data due to intratumoral HER2 heterogeneity. Of note, in HER2 IHC3+ cases with negative drPCR results, re-evaluation of IHC using an artificial intelligence (AI)-based HER2 scoring system revised the HER2 IHC 3+ score to 2+, and ISH assessment also confirmed that these cases are indeed HER2-negative, proving the high accuracy of HER2 CN drPCR assay. In conclusion, given the advantages of drPCR-based HER2 assessment with high accuracy, sensitivity, and simplicity, the drPCR assay could be a complementary or alternative method to IHC and ISH to greatly improve current HER2 testing. Citation Format: Jin hyuk Chang, YoonSik Kim, Hee-Joo Choi, Soo Young Park, Ji-Hye Park, Hee-Young Won, Min Ji Song, Da Sol Kim, Hayeon Kim, Sohyeon Yang, Nam Hun Heo, Minsik Song, Seung-Shick Shin, Do Young Lee, Han Suk Ryu, Si-Hyong Jang, Jeong-Yeon Lee. Ultra-rapid and precise measurement of HER2 copy number alteration by next-generation digital PCR capable of real-time analysis in patients with breast cancer: A multicenter retrospective study [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr A005.

Lee Ah Young;Kim Min Ji;Kim Se Hyun;Yang Yeong Ae

Lee Ah Young;Kim Min Ji;Kim Se Hyun;Yang Yeong Ae

Abstract LB168: Efficacy analysis of the DeepNeo neoantigen prediction tool for antitumor vaccine development

Abstract Antitumor peptide vaccine is an alternative and attractive way to eradicate tumors by the aid of host immune system. The current peptide vaccine development is hampered by several hurdles. These include heterogeneity of tumor cells, applicable in vivo stability of peptides, and others. One of the major obstacles is the precise prediction of cancer antigen, which can be loaded efficiently onto antigen presenting cells. We present here a neoantigen prediction algorithm DeepNeo comprised of DeepNeo-MHC and DeepNeo-TCR, which calculates the antigenicity of neoantigen based on the MHC binding and TCR activation potential. We examined the efficacy of DeepNeo using ELISPOT and two allogenic mouse tumor models. By treating the combination of long peptides targeting MC38 colon or B16F10 melanoma cell lines, we have shown the DeepNeo effectively determines neoantigens for the development of antitumor peptide vaccine. Analysis of tumor-infiltrated lymphocytes (TIL) supported our results. Undergoing study using patient-derived xenograft model treated with autologous, trained PBMC with personalized peptide vaccine will be discussed further. Citation Format: Eun Ji Lee, Min Ji Park, Soo Jin Kim, Seung-Jae Noh, Inkyung Shin, Jeong Yeon Kim, Incheol Shin, Jung Kyoon Choi, Dae-Yeon Cho, Suhwan Chang. Efficacy analysis of the DeepNeo neoantigen prediction tool for antitumor vaccine development [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB168.

Abstract 3777: MicroRNA-inducible CRISPR/Cas9 for cell type-specific genome regulation in cancer

Abstract MicroRNA-dependent mRNA decay plays an important role in gene silencing by facilitating posttranscriptional and translational repression. Inspired by this intrinsic nature of microRNA-mediated mRNA cleavage, here, we describe a microRNA-targeting mRNA as a switch platform called mRNA bridge mimetics to regulate the translocation of proteins. We applied the mRNA bridge mimetics platform to Cas9 protein to confer it the ability to translocate into the nucleus via cleavage of the nuclear export signal called CRISPR Self Check-In. This system performed programmed gene editing in vitro and in vivo. Combinatorial treatment with cisplatin and miR-21-EZH2 axis-targeting CRISPR Self Check-In improved sensitivity to chemotherapeutic drugs in vivo. Using the endogenous microRNA mediated mRNA decay mechanism, our platform is able to remodel a cell’s natural biology to allow the entry of precise drugs into the nucleus, devoid of non-specific translocation. The mRNA bridge mimetics strategy is promising for applications in which the reaction must be controlled via intracellular stimuli and modulates Cas9 proteins to ensure safe genome modification in diseased conditions. Citation Format: Seung Ja Oh, Cheol-Hee Shin, Ji Min Lee, Juyong Lee, Su Chan Park. MicroRNA-inducible CRISPR/Cas9 for cell type-specific genome regulation in cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3777.

Abstract 1493: ROS inhibits enzymatic activation of PRMT5 and increases the protein stability of tumor suppressors as non-histone substrates in liver cancer

Abstract Retinoic acid receptor-related orphan receptor α (RORα) and p53 are transcription factors involved in nuclear gene expression and known tumor suppressors. RORα was the first identified substrate of lysine methylation-dependent degradation. However, the mechanisms of other post-translational modifications (PTMs) that occur in RORα and p53 remain largely unknown, especially in liver cancer. Arginine methylation is a common PTM in arginine residues of nonhistone and histone proteins and affects substrate protein function and fate. We found an analogous amino acid disposition containing R37 at the ROR N-terminus compared to histone H3 residue, which is arginine methylated. Here, we provide evidence that R37 methylation-dependent degradation is carried out by protein arginine methyltransferase 5 (PRMT5). In addition, we discovered that PRMT5 regulated the interaction between the E3 ubiquitin ligase ITCH and RORα through RORα arginine methylation. Arginine methylation-dependent ubiquitination-mediated RORα degradation reduced downstream target gene activation. H2O2-induced reactive oxygen species (ROS) decreased PRMT5 protein levels, consequently increasing RORα protein levels in liver cancer in vitro and in vivo. Furthermore, the enzymatic activities of PRMT5 were directly affected by ROS via the dissociation of PRMT5-Mep50 octamer in the methylosome complex. Taken together, ROS inhibited liver cancer progression by inducing apoptosis via PRMT5-mediated methylation of RORα combined with other histone and non-histone substrates and the ITCH axis. Our results potentiate PRMT5 as an elimination target in cancer therapy, and this additional regulatory level within ROS signaling may help identify new targets for therapeutic intervention in liver cancer. Citation Format: Ji Min Lee, Hyunkyung Kim, Hyuntae Im, Hee-ji Baek. ROS inhibits enzymatic activation of PRMT5 and increases the protein stability of tumor suppressors as non-histone substrates in liver cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1493.

Abstract 6331: The anti-tumor activity of HSP-90 therapeutic cancer vaccine (AST-021p) combine with TLR2/3 agonist in a MMTV-neu transgenic model

Abstract Background: AST-021p, which is derived from HLA class II binding epitopes of human HSP90 protein, is an investigational therapeutic cancer vaccine for the malignant neoplasms. AST-021p is designed to demonstrate the immunologic efficacy by activating antigen-specific CD4+ Th1 cell in humans. Due to their ability to link the innate with the adaptive immune response, Toll-like receptor (TLR) agonists are highly promising as adjuvants in vaccines against life-threatening and complex diseases such as cancer, AIDS and malaria. In this study, AST-021p was investigated to evaluate the immunogenicity and tumor growth inhibitory effect under the condition of combining with various immune adjuvants derived from TLR agonists, using in-vivo model. Methods: Three different agonists of TLR (TLR-4, TLR-2/3, TLR-7/8) were assigned to investigate the immunogenicity in each group (4 FVB/N mice/group, total 4 groups). AST-021p was intradermally injected 3 times with different TLR-agonists and the immunogenicity was assessed from mouse splenocyte by HSP90-specific IFN-γ ELISpot method. We also examined the efficacy of AST-021p and selected TLR-agonist in MMTV/neu Tg mice (4 mice/group, conducted twice and A total 8 mice was assigned to each group). The combination of AST-021p and TLR-2/3 agonist (AST-021p plus TLR-2/3 agonist) was injected 3 times every 10 days to mice followed by inoculated mouse mammary cancer cell line. The tumor volume change and immunogenicity were evaluated. Results: The most effective TLR-agonist as a potent immune adjuvant was a TLR-2/3 agonist (L-pampoTM, supplied by CHA Vaccine Institute). AST-021p (100 μg) plus TLR-2/3 agonist significantly improved immunogenicity by increasing HSP-90 epitope-specific T cells up to 130±10 per 1x105 spleen cell of FVB/N mice (P<0.001). AST-021p plus TLR-2/3 agonist also showed higher tumor growth inhibitory effect (170±108 mm3) on post-implantation 35th day by suppressing mouse mammary cancer cell line (5x105)-derived tumor growth, compared with a TLR-2/3 agonist alone (1031±450 mm3). Conclusions: Combination regimen of AST-021p and TLR-2/3 agonist (as immune adjuvant) demonstrated significant immunogenicity and tumor prevention effect in in-vivo study. These data supported the clinical study of AST-021p combined with TLR-2/3 agonist as active immune adjuvant in certain tumor types, and phase 1/2 clinical program would be expected to be initiated. Citation Format: JinHo Kang, Jee Hyun Choi, Min Ji Seo, Eunjung Jung, Byung cheol Ahn, Jinback Lim, Hyo-Hyun Park, Hyunwon Shin, Eunkyo Joung, Hun Jung, Kyong Hwa Park. The anti-tumor activity of HSP-90 therapeutic cancer vaccine (AST-021p) combine with TLR2/3 agonist in a MMTV-neu transgenic model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6331.

“Гуулин улсын судар”-ын тухай

History of Goryeo Dynasty is one of the official histories of Korea and included Goryeo Dynasty’s politic, economy, social culture and biography of public figures which is most important fundamental source for our current studying the ancient history of that time. Therefore, many research studies has been made on the History of Goryeo Dynasty in perspective of manuscript study, literature study and culture study in apart from of history, at present in Korea. This source is written right after establishment of Joseon Dynasty as chronicle of the Goryeo Dynasty’s late period, whereas Korean scholars cannot eject view that political justification view point reflected on establishment of Joseon Dynasty.
 However, the Goryeo Dynasty’s all time king’s Joseon wangjo sillok (실록. 實錄Veritable Records of the Joseon Dynasty) was used as the main source of creating the History of Goryeo Dynasty and the people present at that time such as “Comprehensive records arranged by year (편년통록. 編年通錄)” by Kim Kwan-ui (김관의. 金寬毅), “Comprehensive records of Gangmo (편년강목. 編年綱目)” by Min Ji (민지. 閔漬), “Records of reflection from Mirror (금경록. 金鏡錄)” by Yi Saek (이색. 李穡)and Yi Yinbok (이인복. 李仁復), “Sikmok pyeonsurok (식목편수록. 拭目編修錄)” and “Prescribed Ritual Text of the Past and Present (고금상정례. 古今詳定禮)” by Choe Yun-ui(최윤의. 崔允儀), “Ikjae-nango(익재난고. 益齋亂藁)” and “Scribbles of Old Man Oak (역옹패설. 櫟翁稗說)” by Yi Jehyeon (이제현. 李齊賢), and “Jugwanyukik (주관육익. 周官六翼)” by Kim, Goo-Yong(김구용. 金九容) are used as reference. Thus, researchers conclude that it describe assure true history of that period and one can say it elevate the value of the source.

Abstract P2-20-04: Vaccination against HIF1α/c-MET peptides overcome lapatinib resistance and inhibits tumor growth by immunomodulating in HER2 positive breast cancer

Abstract Human Epidermal growth factor Receptor 2 (HER2) is overexpressed in 20% to 30% of breast cancers and is associated with poor prognosis. Patients with advanced HER2-type breast cancer are treated with HER2-directed tyrosine kinase inhibitors as well as antibodies, but many patients finally acquire therapeutic resistance. Therefore, it is important to develop new treatment strategies that circumvent HER2 positive resistant breast cancer. Among the suggested mechanisms of resistance to HER2-targeted therapeutics, tumor hypoxia and relevant biological factors are known as important players. In this study, we aimed to explore the role of tumor hypoxia in the development of resistance to HER2-targeted therapeutics, and whether the role of an immunological therapy targeting this could contribute to overcoming resistance. To this end, we established lapatinib-resistant HER2 positive breast cancer cells in vitro (SKBR3, BT-474 for human and MMC for murine cells). First, we examined if lapatinib-sensitivity is different according to oxygen concentration using lapatinib-resistant cell lines (LR-SKBT3, LR-BT-474, LR-MMC) compared with parent cell lines. Resistant cells were resistant both in normoxic and hypoxic conditions, but parent cells were highly sensitive in both of the oxygen concentration. In the Western blot analysis, HIF1α and c-MET were overexpressed in the resistant cells compared with parent cell lines in both normoxic and hypoxic condition. Interestingly, treatment with lapatinib had reduced HIF1α and c-MET expression at normoxia in parent cell lines but not in resistant cell lines. Under the hypoxic conditions, the difference in expression of HIF1α and c-MET was more pronounced between parent cell lines and resistant cell lines treated with lapatinib. These results indicate that the expression of HIF1α and c-MET was involved in lapatinib-resistant. In a previous study, we have identified epitopes from HIF1α/c-MET and demonstrated effect of delayed bone metastasis in triple negative breast cancer model when used as peptide vaccine. Herein, we evaluated whether the immunization using HIF1α/c-MET peptide vaccine is effective in inhibition of lapatinib-resistant HER2 positive breast cancer growth in vivo. MMTVneu-transgenic mouse model was used and 6- 8 weeks old mice were injected with LR-MMC subcutaneously. Immunization using the HIF1α/c-MET peptide vaccine significantly inhibited growth of LR-MMC cells in MMTVneu-transgenic mice compared with controls. HIF1α/c-MET specific IFN-γ-secreting T cell responses in the splenocytes were significantly higher in the immunized group than controls. Immunohistochemical staining of T cells revealed that expression of tumor HIF1α and c-MET was significantly decreased, while the number of CD8+ T cell was increased in the tumors from immunized animals compared with control tumors. In conclusion, our study demonstrated that the vaccine targeting HIF1α/c-MET might be a promising cancer immunotherapy in lapatinib-resistant HER2 positive breast cancer. In vivo study to evaluate efficacy of combination therapy (lapatinib and HIF1α/c-MET vaccine) is ongoing. Citation Format: Ji Min Lee, Jin Hwa Hong, Soon Young Lim, Ju Won Kim, Ah Reum Lim, Myung Han Hyun, Kyong Hwa Park. Vaccination against HIF1α/c-MET peptides overcome lapatinib resistance and inhibits tumor growth by immunomodulating in HER2 positive breast cancer. [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-20-04.

D–A Type NIR‐II Organic Molecules: Strategies for the Enhancement Fluorescence Brightness and Applications in NIR‐II Fluorescence Imaging‐Navigated Photothermal Therapy (Adv. Healthcare Mater. 21/2022)

Photothermal Therapy In article 2201158 by Peng Wang, Pengfei Sun, Min Ji, and co-workers, some approaches to the development and design strategies of D–A type small molecules and conjugated polymers for the enhancement of fluorescence brightness are systemically introduced. Meanwhile, some applications of photothermal therpy (PTT) and PTT-based combination therapies assisted by NIR-II FI-based single or multiimaging technologies are classified and represented in detail. Finally, the current issues and challenges of NIR-II organic molecules in NIR-II FI-navigated PTT are summarized and discussed.