[Comparative immunohistochemistry study of different antibodies clones for detection of breast cancer markers (estrogen receptor, progesterone receptor, HER2/neu, Ki-67)]. / Sravnitel'noe issledovanie antitel razlichnykh klonov dlya vyyavleniya markerov raka molochnoi zhelezy (retseptorov estrogenov, progesterona, HER2/neu, Ki-67) immunogistokhimicheskim metodom.

OBJECTIVE: A comparative study of detection of breast cancer markers (estrogen receptors, progesterone receptors, HER2/neu, Ki-67) by immunohistochemical method with antibodies produced by PrimeBioMed (Russia) and antibodies produced by Roche Ventana (USA). MATERIAL AND METHODS: Surgical specimens and biopsies from 37 patients with invasive breast cancer were used. Sections were stained with antibodies of clones ER SP1 and GM030, PR 1E2 and PBM-5B8, HER2/neu 4B5 and PBM-46A6, Ki-67 30-9 and GM010. RESULTS: There was a high positive and significant correlation between the immunohistochemistry results and antibodies of the clones ER-SP1 and GM030, PR1E2 and PBM-5B8, HER2/neu4B5 and PBM-46A6, Ki-67 30-9 and GM010. CONCLUSION: The study showed the possibility of using antibodies of clones GM030, HER2/neu 4B5, PBM-46A6, GM010 (PrimeBioMed) on the Ventana Bench Marck Ultra automatic immunostainer using the detection system UltraView Universal DAB Detection Kit.

Lapatinib antitumor effect is associated with PI3K and MAPK pathway: An analysis in human and canine prostate cancer cells.

The aberrant activation of HER2 has a pivotal role in bone metastasis implantation and progression in several tumor types, including prostate cancer (PC). Trastuzumab and other anti-HER2 therapies, such as lapatinib, have been used in human breast cancer HER2 positive. Although HER2 overexpression has been reported in PC, anti-HER2 therapy response has revealed conflicting results. We investigated the potential of lapatinib in inhibiting cell migration and inducing apoptosis in two human (LNCaP and PC3) and two canine PC cell lines (PC1 and PC2). Cell migration and apoptosis were evaluated by Annexin V/PI analysis after lapatinib treatment. The transcriptome analysis of all cell lines before and after treatment with lapatinib was also performed. We found increased apoptosis and migration inhibition in LNCaP cells (androgen-sensitive cell line), while PC1, PC2, and PC3 cells showed no alterations after the treatment. The transcriptome analysis of LNCaP and PC3 cell lines showed 158 dysregulated transcripts in common, while PC1 and PC2 cell lines presented 82. At the doses of lapatinib used, we observed transcriptional modifications in all cell lines. PI3K/AKT/mTOR pathway were enriched in human PC cells, while canine PC cells showed enrichment of tyrosine kinase antitumor response and HER2-related pathways. In canine PC cells, the apoptosis failed after lapatinib treatment, possibly due to the downregulation of MAPK genes. Prostate cancer cells insensitive to androgens may be resistant to lapatinib through PI3K gene dysregulation. The association of lapatinib with PI3K inhibitors may provide a more effective antitumor response and clinical benefits to PC patients.

Tucatinib Combination Treatment After Trastuzumab-Deruxtecan in Patients With ERBB2-Positive Metastatic Breast Cancer.

Importance: Little is known regarding the outcomes associated with tucatinib combined with trastuzumab and capecitabine (TTC) after trastuzumab-deruxtecan exposure among patients with ERBB2 (previously HER2)-positive metastatic breast cancer (MBC). Objective: To investigate outcomes following TTC treatment in patients with ERBB2-positive MBC who had previously received trastuzumab-deruxtecan. Design, Setting, and Participants: This cohort study included all patients with MBC who were treated in 12 French comprehensive cancer centers between August 1, 2020, and December 31, 2022. Exposure: Tucatinib combined with trastuzumab and capecitabine administered at the recommended dose. Main Outcomes and Measures: Clinical end points included progression-free survival (PFS), time to next treatment (TTNT), overall survival (OS), and overall response rate (ORR). Results: A total of 101 patients with MBC were included (median age, 56 [range, 31-85] years). The median number of prior treatment lines for metastatic disease at TTC treatment initiation was 4 (range, 2-15), including 82 patients (81.2%) with previous trastuzumab and/or pertuzumab and 94 (93.1%) with previous ado-trastuzumab-emtansine) exposure. The median duration of trastuzumab-deruxtecan treatment was 8.9 (range, 1.4-25.8) months, and 82 patients (81.2%) had disease progression during trastuzumab-deruxtecan treatment, whereas 18 (17.8%) had stopped trastuzumab-deruxtecan for toxic effects and 1 (1.0%) for other reasons. Tucatinib combined with trastuzumab and capecitabine was provided as a third- or fourth-line treatment in 37 patients (36.6%) and was the immediate treatment after trastuzumab-deruxtecan in 86 (85.1%). With a median follow-up of 11.6 (95% CI, 10.5-13.4) months, 76 of 101 patients (75.2%) stopped TTC treatment due to disease progression. The median PFS was 4.7 (95% CI, 3.9-5.6) months; median TTNT, 5.2 (95% CI, 4.5-7.0) months; and median OS, 13.4 (95% CI, 11.1 to not reached [NR]) months. Patients who received TTC immediately after trastuzumab-deruxtecan had a median PFS of 5.0 (95% CI, 4.2-6.0) months; median TTNT of 5.5 (95% CI, 4.8-7.2) months, and median OS of 13.4 (95% CI, 11.9-NR) months. Those who received TTC due to trastuzumab-deruxtecan toxicity-related discontinuation had a median PFS of 7.3 (95% CI, 3.0-NR) months. Best ORR was 29 of 89 patients (32.6%). Sixteen patients with active brain metastasis had a median PFS of 4.7 (95% CI, 3.0-7.3) months, median TTNT of 5.6 (95% CI, 4.4 to NR), and median OS of 12.4 (95% CI, 8.3-NR) months. Conclusions and Relevance: In this study, TTC therapy was associated with clinically meaningful outcomes in patients with ERBB2-positive MBC after previous trastuzumab-deruxtecan treatment, including those with brain metastases. Prospective data on optimal drug sequencing in this rapidly changing therapeutic landscape are needed.

Exploring the effectiveness of molecular subtypes, biomarkers, and genetic variations as first-line treatment predictors in Asian breast cancer patients: a systematic review and meta-analysis.

BACKGROUND: Breast cancer incidence has been on the rise significantly in the Asian population, occurring at an earlier age and a later stage. The potential predictive value of molecular subtypes, biomarkers, and genetic variations has not been deeply explored in the Asian population. This study evaluated the effect of molecular subtype classification and the presence or absence of biomarkers and genetic variations on pathological complete response (pCR) after neoadjuvant treatment in Asian breast cancer patients. METHODS: A systematic search was conducted in MEDLINE (PubMed), Science Direct, Scopus, and Cochrane Library databases. Studies were selected if they included Asian breast cancer patients treated with neoadjuvant chemotherapy and contained data for qualitative or quantitative analyses. The quality of the included studies was assessed using the Newcastle Ottawa Scale. Following the random effects model, pooled odds ratios or hazard ratios with 95% confidence intervals for pCR were analysed using Review Manager Software. Heterogeneity between studies was assessed using Cochran's Q-test and I2 test statistics. RESULTS: In total, 19,708 Asian breast cancer patients were pooled from 101 studies. In the neoadjuvant setting, taxane-anthracycline (TA) chemotherapy showed better pCR outcomes in triple-negative breast cancer (TNBC) (p<0.0001) and human epidermal growth factor receptor 2 enriched (HER2E) (p<0.0001) than luminal breast cancer patients. Similarly, taxane-platinum (TP) chemotherapy also showed better pCR outcomes in TNBC (p<0.0001) and HER2E (p<0.0001). Oestrogen receptor (ER)-negative, progesterone receptor (PR)-negative, HER2-positive and high Ki-67 were significantly associated with better pCR outcomes when treated with either TA or TP. Asian breast cancer patients harbouring wildtype PIK3CA were significantly associated with better pCR outcomes when treated with TA in the neoadjuvant setting (p=0.001). CONCLUSIONS: In the neoadjuvant setting, molecular subtypes (HER2E and TNBC), biomarkers (ER, PR, HER2, HR, Ki-67, nm23-H1, CK5/6, and Tau), and gene (PIK3CA) are associated with increased pCR rates in Asian breast cancer patients. Hence, they could be further explored for their possible role in first-line treatment response, which can be utilised to treat breast cancer more efficiently in the Asian population. However, it needs to be further validated with additional powered studies. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42021246295.

PRaG 3.0 therapy for human epidermal growth factor receptor 2-positive metastatic pancreatic ductal adenocarcinoma: A case report.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a highly fatal disease with limited effective treatment especially after first-line chemotherapy. The human epidermal growth factor receptor 2 (HER-2) immunohistochemistry (IHC) positive is associated with more aggressive clinical behavior and shorter overall survival in PDAC. CASE SUMMARY: We present a case of multiple metastatic PDAC with IHC mismatch repair proficient but HER-2 IHC weakly positive at diagnosis that didn't have tumor regression after first-line nab-paclitaxel plus gemcitabine and PD-1 inhibitor treatment. A novel combination therapy PRaG 3.0 of RC48 (HER2-antibody-drug conjugate), radiotherapy, PD-1 inhibitor, granulocyte-macrophage colony-stimulating factor and interleukin-2 was then applied as second-line therapy and the patient had confirmed good partial response with progress-free-survival of 6.5 months and overall survival of 14.2 month. She had not developed any grade 2 or above treatment-related adverse events at any point. Percentage of peripheral CD8+Temra and CD4+Temra were increased during first two activation cycles of PRaG 3.0 treatment containing radiotherapy but deceased to the baseline during the maintenance cycles containing no radiotherapy. CONCLUSION: PRaG 3.0 might be a novel strategy for HER2-positive metastatic PDAC patients who failed from previous first-line approach and even PD-1 immunotherapy but needs more data in prospective trials.

Telangiectasias induced by combination tucatinib and ado-trastuzumab emtansine in a patient with metastatic breast cancer.

BACKGROUND: Tucatinib is a tyrosine kinase inhibitor currently used in salvage therapy for human epidermal growth factor receptor 2 (HER2)-positive breast and colorectal cancer. The use of tucatinib alone or in combination with ado-trastuzumab emtansine (T-DM1) in the treatment of advanced HER2-positive cancers is rapidly expanding. OBJECTIVE/METHODS: We report the case of a 66-year-old female who presented to the dermatology clinic with a one-year history of widespread telangiectasias that began after initiation of combination chemotherapy with tucatinib and T-DM1 for metastatic HER2-positive invasive ductal carcinoma. RESULTS: The patient's lesions regressed upon cessation of combination therapy and reappeared in the setting of tucatinib re-initiation, with gradual improvement over the following four months following electrocautery to the affected regions. CONCLUSIONS: We postulate that telangiectasias may be a previously unreported dermatologic side effect of combination treatment with tucatinib and T-DM1. Electrocautery is a safe and effective procedure to reduce the appearance of telangiectasias and improve patient satisfaction during chemotherapy.

Adjuvant Chemotherapy in Premenopausal Patients With Hormone-Positive Breast Cancer With a Recurrence Score of 16-25: A Retrospective Analysis Using the National Cancer Database.

PURPOSE: Results from the TAILORx trial revealed that the use of adjuvant chemotherapy along with endocrine therapy had no survival advantage in patients with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2-negative (HER2-), node-negative (N0) breast cancer (BC) with an intermediate (11-25) 21-gene recurrence score (RS) in the overall population. However, in patients under age 50 years, adjuvant chemotherapy demonstrated a progression-free survival benefit when the RS ranged from 16-25. We studied this cohort with the population-based national database. METHODS: The 2010-2018 National Cancer Database was used to include patients with BC age 18-50 years, N0, M0, RS 16-25, ER+/progesterone receptor±, and HER2-. Patients were divided into two groups on the basis of adjuvant chemotherapy use, and the survival between them was compared. RESULTS: Adjuvant chemotherapy use was noted in 4,808/15,792 (30.45%) patients. Median RS was 18 and 21 in patients without and with adjuvant chemotherapy, respectively. Factors associated with adjuvant chemotherapy use were higher T stage, poor and moderately differentiated tumors, age <40 years, care at an academic center, Caucasian race, patients undergoing mastectomy, regional lymph node surgery, and radiation therapy. Kaplan-Meier survival at 10 years was better with adjuvant chemotherapy (96.2% v 91.6%). Patients without adjuvant chemotherapy had more adverse outcomes (hazard ratio [HR], 1.683 [95% CI, 1.392 to 2.036]; P < .0001). Subgroup analysis showed that the benefit was significant in patients with RS scores 21-25 (HR, 1.953 [95% CI, 1.295 to 2.945]), ductal histology (HR, 1.521 [95% CI, 1.092 to 2.118]), Caucasian race (HR, 1.655 [95% CI, 1.180 to 2.322]), and 41-50 years age group (HR, 1.732 [95% CI, 1.244 to 2.411]). CONCLUSION: Our study showed an overall survival benefit for adjuvant chemotherapy use in patients with ER-positive, N0 premenopausal BC patients, age less than 50 years, with an intermediate RS score, particularly 21-25.

Establishment of a Novel Cancer-Specific Anti-HER2 Monoclonal Antibody H2Mab-250/H2CasMab-2 for Breast Cancers.

Overexpression of human epidermal growth factor receptor 2 (HER2) in breast and gastric cancers is an important target for monoclonal antibody (mAb) therapy. All therapeutic mAbs, including anti-HER2 mAbs, exhibit adverse effects probably due to the recognition of antigens expressed in normal cells. Therefore, tumor-selective or specific mAbs can be beneficial in reducing the adverse effects. In this study, we established a novel cancer-specific anti-HER2 monoclonal antibody, named H2Mab-250/H2CasMab-2 (IgG1, kappa). H2Mab-250 reacted with HER2-positive breast cancer BT-474 and SK-BR-3 cells. Importantly, H2Mab-250 did not react with nontransformed normal epithelial cells (HaCaT and MCF 10A) and immortalized normal epithelial cells in flow cytometry. In contrast, most anti-HER2 mAbs, such as H2Mab-119 and trastuzumab reacted with both cancer and normal epithelial cells. Immunohistochemical analysis demonstrated that H2Mab-250 possesses much higher reactivity to the HER2-positive breast cancer tissues compared with H2Mab-119, and did not react with normal tissues, including heart, breast, stomach, lung, colon, kidney, and esophagus. The epitope mapping demonstrated that the Trp614 of HER2 domain IV mainly contributes to the recognition by H2Mab-250. H2Mab-250 could contribute to the development of chimeric antigen receptor-T or antibody-drug conjugates without adverse effects for breast cancer therapy.

Human epidermal growth factor receptor-2 expression and subsequent dynamic changes in patients with ovarian cancer.

Human epidermal growth factor receptor-2 (HER2)-targeting drugs are increasingly being incorporated into therapeutic paradigms for non-breast cancers, yet studies on HER2 expression in ovarian cancer (OC) are inadequate. Here, we studied the HER2 status and dynamic changes in OC by reviewing the records of patients who underwent HER2 testing at a single institution. Clinical parameters, including histology, BRCA status, and immunohistochemistry (IHC), were evaluated alongside HER2 expression, timing, and anatomical location. Among 200 patients, 28% and 6% exhibited expression scores of 2+ and 3+, respectively. HER2 3+ scores were observed in 23%, 11%, 9%, and 5% of mucinous, endometrioid, clear cell, and high-grade serous tumors, respectively, and were exclusively identified in BRCA-wildtype, mismatch repair-proficient, or PD-L1-low-expressing tumors. The TP53 mutation rate was low, whereas ARID1A, KRAS, and PIK3CA mutations were relatively more prevalent with HER2 scores of 2+ or 3+ than with 0 or 1+. Four of the five tumors with an HER2 3+ score exhibited ERBB2 amplification. Among 19 patients who underwent multiple time-lagged biopsies, 11 showed increased HER2 expression in subsequent biopsies. Patients with HER2-overexpressing OC exhibited distinct histological, IHC, and genomic profiles. HER2-targeting agents are potential options for BRCA-wildtype patients, particularly as later lines of treatment.

Neoadjuvant pertuzumab plus trastuzumab in combination with chemotherapy for human epidermal growth factor receptor 2 positive breast cancer: a real-world retrospective single-institutional study in China.

INTRODUCTION: Real-world studies on neoadjuvant dual anti-HER2 therapy combined with chemotherapy for breast cancer (BC) are scarce in China. This study aimed to evaluate the efficacy and safety of neoadjuvant dual anti-HER2 therapy combined with chemotherapy in a real-world setting. Moreover, differences in estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and proliferation cell nuclear antigen (Ki-67) expression pre- and post-neoadjuvant therapy were analyzed. METHODS: Clinical and pathological data of patients with HER2-positive BC who received neoadjuvant dual anti-HER2 therapy combined with chemotherapy at Liaoning Cancer Hospital & Institute, China, between September 2021 and September 2023, were retrospectively reviewed. RESULTS: Among 179 included patients, a pathologic complete response (pCR) was achieved in 109 patients (60.9%). The univariate analysis results indicated that the hormone receptor (HR) status (P = 0.013), HER2 status (P = 0.003), and cycles of targeted treatment (P = 0.035) were significantly correlated with pCR. Subsequent multivariable analysis showed that HR negative and HER2 status 3 + were independent predictive factors of pCR. Anemia was the most common adverse event (62.0%), and the most common grade 3-4 adverse event was neutropenia (6.1%). The differences in HER2 (34.5%) and Ki-67 (92.7%) expression between core needle biopsy and the residual tumor after neoadjuvant therapy were statistically significant, whereas the differences were insignificant in terms of ER or PR status. CONCLUSIONS: The combination of neoadjuvant trastuzumab and pertuzumab with chemotherapy showed good efficiency, and the toxic side effects were tolerable in patients with BC. In cases where pCR was not achieved after neoadjuvant therapy, downregulation of HER2 and Ki-67 expressions was observed.

Universal CAR T cells targeted to HER2 with a biotin-trastuzumab soluble linker penetrate spheroids and large tumor xenografts that are inherently resistant to trastuzumab mediated ADCC.

CAR T cell therapies face challenges in combating solid tumors due to their single-target approach, which becomes ineffective if the targeted antigen is absent or lost. Universal CAR T cells (UniCAR Ts) provide a promising solution by utilizing molecular tags (linkers), such as biotin conjugated to monoclonal antibodies, enabling them to target a variety of tumor antigens. Recently, we showed that conventional CAR T cells could penetrate the extracellular matrix (ECM) of ADCC-resistant tumors, which forms a barrier to therapeutic antibodies. This finding led us to investigate whether UniCAR T cells, targeted by soluble antibody-derived linkers, could similarly tackle ADCC-resistant tumors where ECM restricts antibody penetration. We engineered UniCAR T cells by incorporating a biotin-binding monomeric streptavidin 2 (mSA2) domain for targeting HER2 via biotinylated trastuzumab (BT). The activation and cytotoxicity of UniCAR T cells in the presence or absence of BT were evaluated in conventional immunoassays. A 3D spheroid coculture was set up to test the capability of UniCAR Ts to access ECM-masked HER2+ cells. For in vivo analysis, we utilized a HER2+ xenograft model in which intravenously administered UniCAR T cells were supplemented with intraperitoneal BT treatments. In vitro, BT-guided UniCAR T cells showed effective activation and distinct anti-tumor response. Upon target recognition, IFNγ secretion correlated with BT concentration. In the presence of BT, UniCAR T cells effectively penetrated HER2+ spheroids and induced cell death in their core regions. In vivo, upon intravenous administration of UniCAR Ts, circulating BT linkers immediately engaged the mSA2 domain and directed effector cells to the HER2+ tumors. However, these co-treated mice died early, possibly due to the lung infiltration of UniCAR T cells that could recognize both native biotin and HER2. Our results suggest that UniCAR T cells guided with soluble linkers present a viable alternative to conventional CAR T cells, especially for patients resistant to antibody therapy and those with solid tumors exhibiting high antigenic variability. Critical to their success, however, is the choice of an appropriate binding domain for the CAR and the corresponding soluble linker, ensuring both efficacy and safety in therapeutic applications.

Mutational Analysis of Circulating Tumor DNA in Patients With Estrogen Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Advanced Breast Cancer Receiving Palbociclib: Results From the TREnd Trial.

PURPOSE: To identify prognostic circulating biomarkers to cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i), we performed a mutational analysis on circulating tumor DNA (ctDNA) samples from patients included in the TREnd trial, which randomly assigned patients to receive the CDK4/6i palbociclib alone or with the endocrine treatment (ET) to which they had progressed. METHODS: Forty-six patients were enrolled in this substudy. Plasma was collected before treatment (T0), after the first cycle of therapy (T1), and at the time of progression (T2). ctDNA hybridization and capture were performed using the Illumina TruSight Tumor 170 Kit. Acquired mutations were confirmed by digital polymerase chain reaction. Progression-free survival analysis was estimated using the Kaplan-Meier method and compared with the log-rank test. RESULTS: The most frequently mutated genes at T0 were ESR1 (23%), PIK3CA (17%), AR, FGFR2, and TP53 (10%). Mutations in ESR1 at T0 conferred higher risk of progression in the entire population (P = .02) and in patients treated with palbociclib + ET (P = .04). ESR1 mutation effect remained significant after correction for clinical variables (P = .03). PIK3CA mutations at T0 were not prognostic, but higher risk of progression was observed when a broader analysis of PI3K pathway was performed (P = .04). At T2, we observed the emergence of nine new mutations in seven genes. CONCLUSION: Mutations in ESR1 and in PI3K pathway genes at T0 were associated with worse prognosis in palbociclib-treated patients. We describe the emergence of newly acquired mutations in palbociclib-treated patients, which might potentially affect subsequent treatment.

Breast Cancer Molecular Subtyping in Practice: A Real-World Study of the APIS Breast Cancer Subtyping Assay in a Consecutive Series of Breast Core Biopsies.

The APIS Breast Cancer Subtyping Kit is an mRNA-based assessment of the seven parameters including three biomarkers routinely assessed in all the newly diagnosed breast cancers (BC), oestrogen receptor (ER), progesterone receptor (PR) and HER-2 and an additional four genes that create a novel proliferation signature, MKI67, PCNA, CCNA2 and KIF23. Taken together, the data are used to produce a molecular subtype for every sample. The kit was evaluated against the current standard protocol of immunohistochemistry (IHC) and/or in situ hybridisation (ISH) in breast cancer patients. The data were presented at the weekly breast multidisciplinary team (MDT) meeting. A total of 98 consecutive cases of pre-operative breast cancer core biopsies and two core biopsies of nodal metastases yielding 100 cases were assessed. IHC and APIS results were available for 100 and 99 cases. ER was concordant in 97% cases, PR was concordant in 89% and HER-2 results were concordant with IHC/ISH in 100% of the cases. Ki-67 IHC was discordant in 3% of cases when compared with MK167 alone but discordant in 24% when compared with the four-gene proliferation signature. In conclusion, our study indicates that the APIS Breast Cancer Subtyping Kit is highly concordant when compared to the results produced for ER/PR/HER-2 by IHC and/or ISH. The assay could play a role in the routine assessment of newly diagnosed breast cancer (BC) specimens.

Treatment patterns and clinical outcomes of chidamide combined with endocrine therapy in hormone receptor-positive, HER2-negative metastatic breast cancer: A real-world multicenter study.

BACKGROUND: Chidamide is a selective histone deacetylase inhibitor approved for patients with hormone receptor (HoR)-positive and HER2-negative metastatic breast cancer (MBC). We aimed to investigate the efficacy, safety, and treatment patterns of chidamide and identify clinicopathological factors that predict the efficacy of chidamide in real-world scenarios. METHODS: Consecutive MBC patients treated with chidamide from January 2020 to August 2021 across 11 institutions were enrolled in this multicenter, retrospective study. Eligible patients were pre- and postmenopausal women who had clinically or histologically confirmed ER-positive, HER2-negative MBC, and Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. Patients with multiple primary malignancies or missing baseline characteristics were excluded. Patients received 30 mg chidamide orally twice a week, combined with aromatase inhibitors (AIs) or non-AIs. Efficacy analyses included progression-free survival (PFS), objective response rate (ORR), and clinical benefit rate (CBR). Univariate and multivariate Cox regression analyses were performed to identify the potential efficacy predictors. RESULTS: A total of 157 patients were finally included for analysis. The median number of lines prior to chidamide was four. In the whole cohort, the median PFS was 4.2 months (95% confidence interval [CI] 3.8-4.5). The ORR was 7.5% and the CBR was 31.3%. The efficacy of chidamide was consistent in patients pretreated with CDK4/6 inhibitors and patients treated with different endocrine combinations. Multivariate analysis indicated that patients who had liver metastases (adjusted HR = 1.66, 95% CI 1.14-2.43, adjusted p = 0.008) or ≥3 prior lines of treatment (adjusted HR = 1.80, 95% CI 1.17-2.77, adjusted p = 0.008) had significantly worse PFS. The most common AEs with chidamide were thrombocytopenia, leucopenia, neutropenia, and anemia. CONCLUSION: This study provided real-world data for the use of chidamide in patients with HoR-positive and HER2-negative MBC. Our data endorsed the use of chidamide in patients pretreated with CDK4/6 inhibitors and patients treated with different endocrine combinations.

Molecular probes targeting HER2 PET/CT and their application in advanced breast cancer.

PURPOSE: Human epidermal growth factor receptor 2 (HER2)-positive breast cancer cases are among the most aggressive breast tumor subtypes. Accurately assessing HER2 expression status is vital to determining whether patients will benefit from targeted anti-HER2 treatment. HER2-targeted positron emission tomography (PET/CT) is noninvasive, enabling the real-time evaluation of breast cancer patient HER2 status with accuracy. METHODS: We summarize the research progress of PET/CT targeting HER2 in breast cancer, focusing on PET/CT molecular probes targeting HER2 and their clinical application in the management of advanced breast cancer. RESULTS: At present, a variety of different HER2 targeted molecular probes for PET/CT imaging have been developed, including nucleolin-labeled antibodies, antibody fragments, nanobodies, and peptides of various affinities, among others. HER2-targeted PET/CT can relatively accurately evaluate HER2 expression status in advanced breast cancer patients. It has good performance in the early detection of small HER2-positive lesions, evaluation of HER2 status in lesions that cannot be readily biopsied, evaluation of the heterogeneity of multiple metastases, identification of lesions with altered HER2 status, and evaluation of the efficacy of anti-HER2 drugs. CONCLUSION: HER2-targeted PET/CT offers a promising noninvasive approach for real-time assessment of HER2 status，which can be guide targeted treatment for HER2-positive breast cancer patients. Future prospective clinical studies will be invaluable for fully evaluating the importance of HER2-targeted molecular imaging in the management of breast cancer.

[Advances in the treatment of anti-HER-2 antibody drug conjugates in pan-tumor with low HER-2 expression].

Antibody-drug conjugates (ADCs) are drugs that combine monoclonal antibody drugs targeting specific antigens and small molecule cytotoxic drugs through linker molecules. ADCs combine the advantages of high specificity targeting and potent killing effects, achieving precise and efficient targeting of cancer cells. Nowadays, ADCs are one of the hotspots in cancer drug development. Human epidermal growth factor receptor 2 (HER-2) is a known oncogene that can drive the occurrence and development of various types of tumors. HER-2 is also an important tumor target for ADCs approved for solid tumors. Anti-HER-2 ADCs can not only be used to treat HER-2-positive tumors but also effectively target HER-2-low tumors. The emergence of ADCs has broken the traditional classification of HER-2 in tumors, bringing significant treatment breakthroughs for HER-2-low tumors. Anti-HER-2 ADCs are widely used in the treatment of solid tumors and have substantial evidence for HER-2-low tumors. This article presents the progress of various anti-HER-2 ADCs in HER-2-low tumors including breast cancer, gastrointestinal malignancies, urothelial carcinoma, lung cancer. And this article summarizes the current status of preclinical studies, clinical studies, and safety of anti-HER-2 ADCs in order to provide reference for the clinical use of HER-2-low tumors.

Efficacy of tyrosine kinase inhibitors examined by a combination of Raman micro-spectroscopy and a deep wavelet scattering-based multivariate analysis framework.

HER2 is a crucial therapeutic target in breast cancer, and the survival rate of breast cancer patients has increased because of this receptor's inhibition. However, tumors have shown resistance to this therapeutic strategy due to oncogenic mutations that decrease the binding of several HER2-targeted drugs, including lapatinib, and confer resistance to this drug. Neratinib can overcome this drug resistance and effectively inhibit HER2 signaling and tumor growth. In the present study, we examined the efficacy of lapatinib and neratinib using breast cancer cells by Raman microscopy combined with a deep wavelet scattering-based multivariate analysis framework. This approach discriminated between control cells and drug-treated cells with high accuracy, compared to classical principal component analysis. Both lapatinib and neratinib induced changes in the cellular biochemical composition. Furthermore, the Raman results were compared with the results of several in vitro assays. For instance, drug-treated cells exhibited (i) inhibition of ERK and AKT phosphorylation, (ii) inhibition of cellular proliferation, (iii) cell-cycle arrest, and (iv) apoptosis as indicated by western blotting, real-time cell analysis (RTCA), cell-cycle analysis, and apoptosis assays. Thus, the observed Raman spectral changes are attributed to cell-cycle arrest and apoptosis. The results also indicated that neratinib is more potent than lapatinib. Moreover, the uptake and distribution of lapatinib in cells were visualized through its label-free marker bands in the fingerprint region using Raman spectral imaging. These results show the prospects of Raman microscopy in drug evaluation and presumably in drug discovery.

Exemestane plus everolimus and palbociclib in metastatic breast cancer: clinical response and genomic/transcriptomic determinants of resistance in a phase I/II trial.

The landscape of cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) resistance is still being elucidated and the optimal subsequent therapy to overcome resistance remains uncertain. Here we present the final results of a phase Ib/IIa, open-label trial (NCT02871791) of exemestane plus everolimus and palbociclib for CDK4/6i-resistant metastatic breast cancer. The primary objective of phase Ib was to evaluate safety and tolerability and determine the maximum tolerated dose/recommended phase II dose (100 mg palbociclib, 5 mg everolimus, 25 mg exemestane). The primary objective of phase IIa was to determine the clinical benefit rate (18.8%, n = 6/32), which did not meet the predefined endpoint (65%). Secondary objectives included pharmacokinetic profiling (phase Ib), objective response rate, disease control rate, duration of response, and progression free survival (phase IIa), and correlative multi-omics analysis to investigate biomarkers of resistance to CDK4/6i. All participants were female. Multi-omics data from the phase IIa patients (n = 24 tumor/17 blood biopsy exomes; n = 27 tumor transcriptomes) showed potential mechanisms of resistance (convergent evolution of HER2 activation, BRAFV600E), identified joint genomic/transcriptomic resistance features (ESR1 mutations, high estrogen receptor pathway activity, and a Luminal A/B subtype; ERBB2/BRAF mutations, high RTK/MAPK pathway activity, and a HER2-E subtype), and provided hypothesis-generating results suggesting that mTOR pathway activation correlates with response to the trial's therapy. Our results illustrate how genome and transcriptome sequencing may help better identify patients likely to respond to CDK4/6i therapies.

Systemic immune-inflammation index as a prognostic marker in HER2-positive breast cancer patients undergoing trastuzumab therapy.

The prognostic value of SII (Systemic Immune-Inflammation Index) in HER-2-positive breast cancer (BC) patients, regardless of whether they receive trastuzumab treatment, and its potential value to distinguish patients who may benefit from trastuzumab therapy, warrant further investigation. Clinical data was collected from 797 HER-2-positive BC patients between July 2013 and March 2018. Baseline data differences were adjusted with propensity score matching. Univariate and multivariate analyses explored the correlation between clinical pathological factors, SII, and DFS. Four groups were established. Based on the baseline SII values of the participants, patients who did not receive trastuzumab treatment were divided into Group 1 (Low-SII) and Group 2 (High-SII), where SII had no predictive value for prognosis between groups. Participants who received trastuzumab treatment were also divided into two groups: the Low-SII group (Group 3) and the High-SII group (Group 4). The 5-year DFS was significantly higher in Group 3 than in Group 4 (91.76% vs. 82.76%, P = 0.017). Furthermore, multivariate analysis demonstrated a significant association between high SII and shorter DFS (HR = 3.430, 95% CI = 1.830-6.420, P < 0.001). In HER-2-positive BC patients treated with trastuzumab, those with lower SII showed a longer DFS, suggesting that SII may help in identifying patients who benefit from trastuzumab therapy.

Ribociclib plus Endocrine Therapy in Early Breast Cancer.

BACKGROUND: Ribociclib has been shown to have a significant overall survival benefit in patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. Whether this benefit in advanced breast cancer extends to early breast cancer is unclear. METHODS: In this international, open-label, randomized, phase 3 trial, we randomly assigned patients with HR-positive, HER2-negative early breast cancer in a 1:1 ratio to receive ribociclib (at a dose of 400 mg per day for 3 weeks, followed by 1 week off, for 3 years) plus a nonsteroidal aromatase inhibitor (NSAI; letrozole at a dose of 2.5 mg per day or anastrozole at a dose of 1 mg per day for ≥5 years) or an NSAI alone. Premenopausal women and men also received goserelin every 28 days. Eligible patients had anatomical stage II or III breast cancer. Here we report the results of a prespecified interim analysis of invasive disease-free survival, the primary end point; other efficacy and safety results are also reported. Invasive disease-free survival was evaluated with the use of the Kaplan-Meier method. The statistical comparison was made with the use of a stratified log-rank test, with a protocol-specified stopping boundary of a one-sided P-value threshold of 0.0128 for superior efficacy. RESULTS: As of the data-cutoff date for this prespecified interim analysis (January 11, 2023), a total of 426 patients had had invasive disease, recurrence, or death. A significant invasive disease-free survival benefit was seen with ribociclib plus an NSAI as compared with an NSAI alone. At 3 years, invasive disease-free survival was 90.4% with ribociclib plus an NSAI and 87.1% with an NSAI alone (hazard ratio for invasive disease, recurrence, or death, 0.75; 95% confidence interval, 0.62 to 0.91; P = 0.003). Secondary end points - distant disease-free survival and recurrence-free survival - also favored ribociclib plus an NSAI. The 3-year regimen of ribociclib at a 400-mg starting dose plus an NSAI was not associated with any new safety signals. CONCLUSIONS: Ribociclib plus an NSAI significantly improved invasive disease-free survival among patients with HR-positive, HER2-negative stage II or III early breast cancer. (Funded by Novartis; NATALEE ClinicalTrials.gov number, NCT03701334.).