Quercetin inhibits truncated isoform of dopamine-and cAMP-regulated phosphoprotein as adjuvant treatment for trastuzumab therapy resistance in HER2-positive breast cancer

Trastuzumab resistance is one of the causes of poor prognosis in patients with human epidermal growth factor receptor 2(HER2)-positive(HER2+)breast cancer(BC).The truncated isoform of dopamine-and cAMPregulated phosphoprotein(t-DARPP)has been reported to be involved in trastuzumab therapy resistance and promoting tumor progression.To evaluate the t-DARPP expression in BC,paired tumors and surrounding normal tissues were analyzed by real-time polymerase chain reaction and confirmed higher DARPP-32 kDa family mRNA expression in HER2+BC tumor tissues.We established 2 patient-derived xenografts(PDX)mice models to test the efficacy of trastuzumab,named model 1(non-responder)and model 2(responder).t-DARPP and p95-HER2 protein-protein interactions were detected in PDX tumor tissue from non-responders using Förster resonance energy transfer assays.Instead,there is no response from the responder.Furthermore,mechanistic studies using transwell and western blot assays demonstrated that t-DARPP could upregulate epithelial-mesenchymal transition signaling proteins,enhance p95-HER2 expression and promote cell migration.We found that quercetin effectively reduced t-DARPP expression in HER2+BC cells.In t-DARPP ShRNA-suppressed cells,quercetin synergistically enhanced trastuzumab-induced apoptotic cell death and G2/M phase arrest.In conclusion,the combination of quercetin and trastuzumab treatment by targeting t-DARPP in HER2+BC patients has the potential as a biomarker for mitigating drug resistance.

Sequential neoadjuvant chemotherapy using pegylated liposomal doxorubicin and cyclophosphamide followed by taxanes with complete trastuzumab and pertuzumab treatment for HER2-positive breast cancer: A phase Ⅱ single-arm study

Objective: Despite cardiotoxicity overlap, the trastuzumab/pertuzumab and anthracycline combination remains crucial due to significant benefits. Pegylated liposomal doxorubicin(PLD), a less cardiotoxic anthracycline, was evaluated for efficacy and cardiac safety when combined with cyclophosphamide and followed by taxanes with trastuzumab/pertuzumab in human epidermal growth factor receptor-2(HER2)-positive early breast cancer(BC).Methods: In this multicenter, phase II study, patients with confirmed HER2-positive early BC received four cycles of PLD(30-35 mg/m^(2)) and cyclophosphamide(600 mg/m^(2)), followed by four cycles of taxanes(docetaxel,90-100 mg/m^(2) or nab-paclitaxel, 260 mg/m^(2)), concomitant with eight cycles of trastuzumab(8 mg/kg loading dose,then 6 mg/kg) and pertuzumab(840 mg loading dose, then 420 mg) every 3 weeks. The primary endpoint was total pathological complete response(tp CR, yp T0/is yp N0). Secondary endpoints included breast p CR(bp CR),objective response rate(ORR), disease control rate, rate of breast-conserving surgery(BCS), and safety(with a focus on cardiotoxicity).Results: Between May 27, 2020 and May 11, 2022, 78 patients were treated with surgery, 42(53.8%) of whom had BCS. After neoadjuvant therapy, 47 [60.3%, 95% confidence interval(95% CI), 48.5%-71.2%] patients achieved tp CR, and 49(62.8%) achieved bp CR. ORRs were 76.9%(95% CI, 66.0%-85.7%) and 93.6%(95% CI,85.7%-97.9%) after 4-cycle and 8-cycle neoadjuvant therapy, respectively. Nine(11.5%) patients experienced asymptomatic left ventricular ejection fraction(LVEF) reductions of ≥10% from baseline, all with a minimum value of >55%. No treatment-related abnormal cardiac function changes were observed in mean N-terminal pro-BNP(NT-pro BNP), troponin I, or high-sensitivity troponin.Conclusions: This dual HER2-blockade with sequential polychemotherapy showed promising activity with rapid tumor regression in HER2-positive BC. Importantly, this regimen showed an acceptable safety profile,especially a low risk of cardiac events, suggesting it as an attractive treatment approach with a favorable risk-benefit balance.

A phase Ⅰ study of Hemay022, an irreversible dual EGFR/HER2 tyrosine kinase inhibitor in Chinese patients with HER2-positive advanced breast cancer

Objective: Hemay022 is a novel small-molecule and an irreversible tyrosine kinase inhibitor with the target of epidermal growth factor receptor(EGFR)/human epidermal growth factor receptor 2(HER2), which demonstrated anti-tumor activity in preclinical studies. This first-in-human study evaluated the safety, pharmacokinetics,tolerability and preliminary anti-tumor activity of Hemay022 in HER2-positive advanced breast cancer patients.Methods: Heavily pretreated patients with HER2-positive advanced breast cancer were assigned to eight dose cohorts in a 3+3 dose-escalation pattern at doses of 50-600 mg QD and 300 mg BID. Eligible patients were given a single dose of Hemay022 on d 1 in week 0, followed by once daily continuous doses for four weeks in 28-day cycles.Pharmacokinetic samples were obtained on d 1 and d 28. Clinical responses were assessed every eight weeks.Results: Twenty-eight patients with advanced breast cancer were treated with Hemay022. The most frequently reported drug-related adverse events were diarrhoea(85.7%), vomiting(28.6%), nausea(25.0%) and decreased appetite(17.9%). No grade 4 drug-related adverse events were reported. At 50-600 mg doses, steady state areas under the concentration-time curve and peak concentrations increased with doses. One patient achieved complete response(CR), and three achieved partial response(PR). The objective response rate(ORR) and disease control rate(DCR) were 14.3% and 46.4% in 28 patients, respectively. The median progression-free survival(PFS) was3.98 months.Conclusions: Hemay022 at the dose of 500 mg once daily was well tolerated. The pharmacokinetic properties and encouraging anti-tumor activities of Hemay022 in advanced breast cancer patients warranted further evaluation of Hemay022 for treating breast cancer patients in the current phase Ⅲ trial(No. NCT05122494).

Ferroptosis biomarkers predict tumor mutation burden's impact on prognosis in HER2-positive breast cancer

BACKGROUND Ferroptosis has recently been associated with multiple degenerative diseases.Ferroptosis induction in cancer cells is a feasible method for treating neoplastic diseases.However,the association of iron proliferation-related genes with prognosis in HER2+breast cancer(BC)patients is unclear.AIM To identify and evaluate fresh ferroptosis-related biomarkers for HER2+BC.METHODS First,we obtained the mRNA expression profiles and clinical information of HER2+BC patients from the TCGA and METABRIC public databases.A four gene prediction model comprising PROM2,SLC7A11,FANCD2,and FH was subsequently developed in the TCGA cohort and confirmed in the METABRIC cohort.Patients were stratified into high-risk and low-risk groups based on their median risk score,an independent predictor of overall survival(OS).Based on these findings,immune infiltration,mutations,and medication sensitivity were analyzed in various risk groupings.Additionally,we assessed patient prognosis by combining the tumor mutation burden(TMB)with risk score.Finally,we evaluated the expression of critical genes by analyzing single-cell RNA sequencing(scRNA-seq)data from malignant vs normal epithelial cells.RESULTS We found that the higher the risk score was,the worse the prognosis was(P<0.05).We also found that the immune cell infiltration,mutation,and drug sensitivity were different between the different risk groups.The highrisk subgroup was associated with lower immune scores and high TMB.Moreover,we found that the combination of the TMB and risk score could stratify patients into three groups with distinct prognoses.HRisk-HTMB patients had the worst prognosis,whereas LRisk-LTMB patients had the best prognosis(P<0.0001).Analysis of the scRNAseq data showed that PROM2,SLC7A11,and FANCD2 were significantly differentially expressed,whereas FH was not,suggesting that these genes are expressed mainly in cancer epithelial cells(P<0.01).CONCLUSION Our model helps guide the prognosis of HER2+breast cancer patients,and its combination with the TMB can aid in more accurate assessment of patient prognosis and provide new ideas for further diagnosis and treatment.

Mechanisms of resistance to trastuzumab in HER2-positive gastric cancer

Gastric cancer is one of the most prevalent cancers worldwide,and human epidermal growth factor receptor 2(HER2)-positive cases account for approximately 20%of the total cases.Currently,trastuzumab+chemotherapy is the recommended first-line treatment for patients with HER2-positive advanced gastric cancer,and the combination has exhibited definite efficacy in HER2-targeted therapy.However,the emergence of drug resistance during treatment considerably reduces its effectiveness;thus,it is imperative to investigate the potential mechanisms underlying resistance.In the present review article,we comprehensively introduce multiple mechanisms underlying resistance to trastuzumab in HER2-positive gastric cancer cases,aiming to provide insights for rectifying issues associated with resistance to trastuzumab and devising subsequent treatment strategies.

Pyrotinib is effective in both trastuzumab-sensitive and primary resistant HER2-positive breast tumors

Objective: Primary resistance to trastuzumab frequently occurs in human epidermal growth factor receptor 2(HER2)-positive(+) breast cancer patients and remains a clinical challenge. Pyrotinib is a novel tyrosine kinase inhibitor that has shown efficacy in the treatment of HER2+ breast cancer. However, the efficacy of pyrotinib in HER2+ breast cancer with primary trastuzumab resistance is unknown.Methods: HER2+ breast cancer cells sensitive or primarily resistant to trastuzumab were treated with trastuzumab, pyrotinib, or the combination. Cell proliferation, migration, invasion, and HER2 downstream signal pathways were analyzed. The effects of pyrotinib plus trastuzumab and pertuzumab plus trastuzumab were compared in breast cancer cells in vitro and a xenograft mouse model with primary resistance to trastuzumab.Results: Pyrotinib had a therapeutic effect on trastuzumab-sensitive HER2+ breast cancer cells by inhibiting phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT) and rat sarcoma virus(RAS)/rapidly accelerated fibrosarcoma(RAF)/mitogen-activated protein kinase(MAPK)/extracellular-signal regulated kinase(ERK)pathways. In primary trastuzumab-resistant cells, pyrotinib inhibited cell growth, migration, invasion, and HER2 downstream pathways, whereas trastuzumab had no effects. The combination with trastuzumab did not show increased effects compared with pyrotinib alone. Compared with pertuzumab plus trastuzumab, pyrotinib plus trastuzumab was more effective in inhibiting cell proliferation and HER2 downstream pathways in breast cancer cells and tumor growth in a trastuzumab-resistant HER2+ breast cancer xenograft model.Conclusions: Pyrotinib-containing treatments exhibited anti-cancer effects in HER2+ breast cancer cells sensitive and with primary resistance to trastuzumab. Notably, pyrotinib plus trastuzumab was more effective than trastuzumab plus pertuzumab in inhibiting tumor growth and HER2 downstream pathways in HER2+ breast cancer with primary resistance to trastuzumab. These findings support clinical testing of the therapeutic efficacy of dual anti-HER2 treatment combining an intracellular small molecule with an extracellular antibody.

A multicenter study on efficacy of dual-target neoadjuvant therapy for HER2-positive breast cancer and a consistent analysis of efficacy evaluation of neoadjuvant therapy by Miller-Payne and RCB pathological evaluation systems(CSBrS-026)

Objective: The aim of this study was to investigate the factors influencing pathological complete response(pCR)rate in early breast cancer patients receiving neoadjuvant dual-target [trastuzumab(H) + pertuzumab(P)] therapy combined with chemotherapy. Additionally, the consistency of the Miller-Payne and residual cancer burden(RCB)systems in evaluating the efficacy of neoadjuvant therapy for early human epidermal growth factor receptor-2(HER2)+ breast cancer was analyzed.Methods: The clinicopathological data of female patients with early-stage HER2+ breast cancer who received dual-target neoadjuvant therapy at 26 hospitals of the Chinese Society of Breast Surgery(CSBrS) from March 2019 to December 2021 were collected. Patients were allocated to four groups: the HER2 immunohistochemistry(IHC)3+/hormone receptor(HR)-, IHC3+/HR+, IHC2+ in situ hybridization(ISH)+/HR-and IHC2+ ISH+/HR+groups. The overall pCR rate for patients, the pCR rate in each group and the factors affecting the pCR rate were analyzed. The consistency between the Miller-Payne and RCB systems in assessing the efficacy of neoadjuvant therapy was analyzed.Results: From March 1, 2019, to December 31, 2021, 77,376 female patients with early-stage breast cancer were treated at 26 hospitals;18,853(24.4%) of these patients were HER2+. After exclusion of unqualified patients, 2,395 patients who received neoadjuvant dual-target(H+P) therapy combined with chemotherapy were included in this study. The overall pCR rate was 53.0%, and the patients' HR statuses and different HER2+ statuses were significantly correlated with the pCR rate(P<0.05). The consistency of the pathological efficacy assessed by the Miller-Payne and RCB systems was 88.0%(κ=0.717, P<0.001).Conclusions: Different HER2 expression statuses and HR expression statuses are correlated with the pCR rate after dual-target neoadjuvant therapy in HER2+ breast cancer patients. There is a relatively good consistency between Miller-Payne and RCB systems in evaluating the pathologic efficacy of neoadjuvant therapy for HER2+breast cancer.

Antibody-Coupled Drugs in HER2-Positive Gastric Cancer

Antibody drug conjugates (ADCs) are a new class of drugs that combine chemosynthetic drugs with antibody drugs through a linker. Antibody drug conjugates combine the targeting characteristics of traditional antibody drugs with the cytotoxic characteristics of small molecule drugs, while reducing the side effects of both drugs, making them a kind of “biological missile” and representing a relatively new and evolving class of anti-cancer drugs. Antibody-coupled drugs are currently used in many solid tumors, and this article reviews the clinical application of antibody-coupled drugs in HER2-positive gastric cancer.

The efficacy of tucatinib-based therapeutic approaches for HER2-positive breast cancer

Overexpression of human epidermal growth factor receptor 2 (HER2) occurs in approximately 15–20% of breast cancer cases. HER2 is a member of the epidermal growth factor receptor (EGFR) family with tyrosinase kinase activity, and its overexpression is linked to poor prognosis and shorter progression-free survival (PFS) and overall survival (OS). Among various treatment options, HER2-targeting monoclonal antibodies and tyrosine kinase inhibitors (TKIs) have mostly been applied in recent decades to treat HER2-positive (HER2^(+)) breast cancer patients. Although positive clinical outcomes were documented in both advanced disease and neoadjuvant settings, the development of resistance mechanisms to such approaches has been one of the major challenges with the continuous usage of these drugs. In addition, patients who experience disease progression after treatment with multiple HER2-targeted therapies often have limited treatment options. The Food and Drug Administration (FDA) has recently approved a new TKI (i.e., tucatinib) for use in combination with immunotherapy and/or chemotherapeutic agents for the treatment of advanced-stage/metastatic HER2^(+) breast cancer. This review highlights recent updates on the efficacy of tucatinib-based therapeutic approaches in experimental models as well as in the clinical settings of HER2^(+) breast cancer.

HER2 heterogeneity is a poor prognosticator for HER2-positive gastric cancer

BACKGROUND The clinical significance of intratumoral human epidermal growth factor receptor 2(HER2)heterogeneity is unclear for HER2-positive gastric cancer,although it has been reported to be a significant prognosticator for HER2-positive breast cancer,which has received trastuzumab-based chemotherapy.AIM To clarify the clinical significance of intratumoral HER2 heterogeneity for HER2-positive gastric cancer,which has received trastuzumab-based chemotherapy.METHODS Patients with HER2-positive unresectable or metastatic gastric cancer who received trastuzumab-based chemotherapy as a first line treatment were included.The patients were classified into two groups according to their intratumoral HER2 heterogeneity status examined by immunohistochemistry(IHC)on endoscopic biopsy specimens before treatment,and their clinical response to chemotherapy and survival were compared.RESULTS A total of 88 patients were included in this study,and HER2 heterogeneity was observed in 23(26%)patients(Hetero group).The overall response rate was significantly better in patients without HER2 heterogeneity(Homo group)(Homo vs Hetero:79.5%vs 35.7%,P=0.002).Progression-free survival of trastuzumab-based chemotherapy was significantly better in the Homo group(median,7.9 vs 2.5 mo,HR:1.905,95%CI:1.109-3.268).Overall survival was also significantly better in the Homo group(median survival time,25.7 vs 12.5 mo,HR:2.430,95%CI:1.389-4.273).Multivariate analysis revealed IHC HER2 heterogeneity as one of the independent poor prognostic factors(HR:3.115,95%CI:1.610-6.024).CONCLUSION IHC of HER2 heterogeneity is the pivotal predictor for trastuzumab-based chemotherapy.Thus,HER2 heterogeneity should be considered during the assessment of HER2 expression.

Preclinical and clinical applications of specific molecular imaging for HER2-positive breast cancer

Precision medicine and personalized therapy are receiving increased attention, and molecular-subtype classification has become crucial in planning therapeutic schedules in clinical practice for patients with breast cancer. Human epidermal growth factor receptor 2(HER2) is associated with high-grade breast tumors, high rates of lymph-node involvement, high risk of recurrence, and high resistance to general chemotherapy. Analysis of HER2 expression is highly important for doctors to identify patients who can benefit from trastuzumab therapy and monitor the response and efficacy of treatment. In recent years, significant efforts have been devoted to achieving specific and noninvasive HER2-positive breast cancer imaging in vivo. In this work, we reviewed existing literature on HER2 imaging in the past decade and summarized the studies from different points of view, such as imaging modalities and HER2-specific probes. We aimed to improve the understanding on the translational process in molecular imaging for HER2 breast cancer.

Non-anthracycline-containing docetaxel and cyclophosphamide regimen is associated with sustained worse outcome compared with docetaxel, anthracycline and cyclophosphamide in neoadjuvant treatment of triple negative and HER2-positive breast cancer patients:

Objective： A previous study demonstrated that non-anthracycline-containing docetaxel plus cyclophosphamide（TC） regimen was inferior to docetaxel, anthracycline and cyclophosphamide（TAC） in neoadjuvant treatment of triple-negative breast cancer（TNBC） and human epidermal growth factor receptor-2-（HER2）-positive breast cancer in a short-term follow-up. Herein, long-term follow-up survival outcomes have been investigated.Methods： TNBC or HER2-positive patients were randomized to receive 6 cycles of TC or TAC neoadjuvant treatment. The primary endpoint was pathological complete remission（p CR）. Secondary endpoints included clinical response rate, event-free survival（EFS）, and overall survival（OS）.Results： A cohort of 96 patients consisted of 45 in TC and 51 in TAC arm. With a median follow-up period of53（range, 8-76） months, the patients achieving p CR post neoadjuvant chemotherapy exhibited superior EFS and OS than patients without p CR（P〈0.05）. TAC treatment resulted in consistently better EFS than TC treatment：the estimated 5-year EFS was 66.1% vs. 29.8%（P=0.002）. Moreover, the estimated 5-year OS was also in favor of TAC： 88.4% vs. 51.6%（P〈0.001）. Multivariable analysis demonstrated that the treatment regimen was an independent prognostic factor, and patients treated with TAC had a superior EFS [hazard ratio（HR）, 0.48; 95%confidence interval（95% CI）, 0.26-0.90; P=0.021] and OS（HR, 0.20; 95% CI, 0.08-0.60; P=0.003）.Conclusions： The updated long-term follow-up data demonstrated a sustained benefit in EFS and OS from anthracycline-containing TAC treatment, indicating that anthracycline is an essential and effective drug in this clinical trial.

HER2-positive adenocarcinoma arising from heterotopic pancreas tissue in the duodenum:A case report

BACKGROUND Adenocarcinoma originating from heterotopic pancreas tissue is a rare disease.Furthermore,to our knowledge,no HER2-positive cases in the duodenum have been reported in the scientific literature nor has the efficacy of trastuzumab treatment for the disease been reported.CASE SUMMARY A 65-year-old woman whose clinical diagnosis was unresectable advanced duodenal cancer with HER2 overexpression responded well to trastuzumab chemotherapy.The main tumor in the duodenum reduced drastically.The patient underwent pancreaticoduodenectomy and lymph node dissection.A small number of cancer cells remained in the submucosal layer of the duodenum and pancreas head.After histological and immunohistochemical examination,the patient was diagnosed with duodenal adenocarcinoma originating from heterotopic pancreas tissue.CONCLUSION Trastuzumab treatment is effective in HER2-positive adenocarcinoma originating from heterotopic pancreas tissue in the duodenum.

HER2-Specific Vaccines for HER2-Positive Breast Cancer Immunotherapy

Anti-human epidermal growth factor receptor-2 (HER2) immunization can be elicited by vaccination with DNA encoding the extra- or intra-cellular domain (ECD or ICD) of HER2, naked or encap-sulated in viral vectors. HER2-peptides derived from ECD or ICD of HER2, and HER2-pulsed dendritic cells (DCs) or engineered DCs expressing HER2, respectively. We performed a computer- based literature search which includes but is not limited to the following keywords: breast cancer, immunotherapy, HER2-peptide vaccine, HER2-DNA vaccine, HER-DC vaccine, HER2 vaccine, and HER2/neu, in PubMed, Medline, EMBO and Google Scholar;data from recently reported clinical trials were also included. Drawing upon this synthesis of literature, this work summarizes the de-velopment and current trend in experimental and clinical investigations in HER2-positive breast cancer using HER2-specific vaccine and immunotherapy, focusing especially on: (i) DNA-;(ii) peptide-;and (iii) DC-based vaccines. It addresses interventions that have been applied to overcome immunotolerance thereby to improve treatment outcomes. These include blocking the inhibitory cytotoxic T lymphocyte-associated protein-4 (CTLA-4), which is expressed at high levels by regulatory T (Treg) cells, or complete Treg depletion to improve T-cell activation. Moreover, modulatory interventions can provide further improvement in the efficacy of HER2-specific vaccine. The interventions include the use of immunogenic adjuvants such as cytokines interleukin-12 (IL-12), tumor necrosis factor (TNF)-α and granulocyte-macrophage colony-stimulating factor (GM-CSF), the use of Toll-like receptor (TLR) ligands and tetanus toxin’s universal epitopes such as the CD4+ help T (Th)-epitope P30, and the use of either chimeric or heterogenous xenogeneic HER2. Combining active HER2-vaccination with adoptive trastuzumab antibody immunotherapy is likely to increase the effectiveness of each approach alone. The development of effective HER2-vaccines for breast cancer remains a critical challenge. Though these novel interventions seem promising, further investigation is still needed since the results are preliminary. Furthermore, the review discusses the challenges and future perspectives in HER2-vaccine research and development.

Inetetamab combined with S-1 and oxaliplatin as first-line treatment for human epidermal growth factor receptor 2-positive gastric cancer

BACKGROUND Patients with human epidermal growth factor receptor 2(HER2)-positive advanced gastric cancer have poor outcomes.Trastuzumab combined with chemotherapy is the first-line standard treatment for HER2-positive advanced gastric cancer.Inetetamab is a novel anti-HER2 drug,and its efficacy and safety in gastric cancer have not yet been reported.AIM To evaluate the efficacy and safety of the S-1 plus oxaliplatin(SOX)regimen combined with inetetamab as a first-line treatment for HER2-positive advanced gastric cancer.METHODS Thirty-eight patients with HER2-positive advanced gastric cancer or gastroeso-phageal junction adenocarcinoma were randomly divided into two groups:One group received inetetamab combined with the SOX regimen,and the other group received trastuzumab combined with the SOX regimen.After 4-6 cycles,patients with stable disease received maintenance therapy.The primary endpoints were progression-free survival(PFS)and overall survival(OS),and the secondary endpoints were the objective response rate,disease control rate,and adverse events(AEs).RESULTS Thirty-seven patients completed the trial,with 18 patients in the inetetamab group and 19 patients in the trastuzumab group.In the inetetamab group,the median PFS was 8.5 months,whereas it was 7.3 months in the trastuzumab group(P=0.046);this difference was significant.The median OS in the inetetamab group vs the trastuzumab group was 15.4 months vs 14.3 months(P=0.33),and the objective response rate was 50%vs 42%(P=0.63),respectively;these differences were not significant.Common AEs included leukopenia,thrombocytopenia,nausea,and vomiting.The incidence rates of grade≥3 AEs were 56%in the inetetamab group and 47%in the trastuzumab group(P=0.63),with no significant difference.CONCLUSION In the first-line treatment of HER2-positive advanced gastric cancer,inetetamab and trastuzumab showed comparable efficacy.The inetetamab group showed superior PFS,and both groups had good safety.

Pyrotinib and chrysin synergistically potentiate autophagy in HER2-positive breast cancer

Human epidermal growth factor receptor 2(HER2)-positive breast cancer(BC)has been the most challenging subtype of BC,consisting of 20%of BC with an apparent correlation with poor prognosis.Despite that pyrotinib,a new HER2 inhibitor,has led to dramatic improvements in prognosis,the efficacy of pyrotinib monotherapy remains largely restricted due to its acquired resistance.Therefore,identifying a new potential antitumor drug in combination with pyrotinib to amplify therapeutic efficacy is a pressing necessity.Here,we reported a novel combination of pyrotinib with chrysin and explored its antitumor efficacy and the underlying mechanism in HER2-positive BC.We determined that pyrotinib combined with chrysin yielded a potent synergistic effect to induce more evident cell cycle arrest,inhibit the proliferation of BT-474 and SK-BR-3 BC cells,and repress in vivo tumor growth in xenograft mice models.This may be attributed to enhanced autophagy induced by endoplasmic reticulum stress.Furthermore,the combined treatment of pyrotinib and chrysin induced ubiquitination and glucose-6-phosphate dehydrogenase(G6PD)degradation by upregulating zinc finger and BTB/POZ domain-containing family protein 16(ZBTB16)in tumorigenesis of BC.Mechanistically,we identified that miR-16-5p was a potential upstream regulator of ZBTB16,and it showed a significant inverse correlation with ZBTB16.Inhibition of miR-16-5p overexpression by restoring ZBTB16 significantly potentiated the overall antitumor efficacy of pyrotinib combined with chrysin against HER2-positive BC.Together,these findings demonstrate that the combined treatment of pyrotinib and chrysin enhances autophagy in HER2-positive BC through an unrecognized miR-16-5p/ZBTB16/G6PD axis.

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),radio-therapy,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.

BIRC3 induces the phosphoinositide 3-kinase-Akt pathway activation to promote trastuzumab resistance in human epidermal growth factor receptor 2-positive gastric cancer

BACKGROUND Trastuzumab-targeted therapy is currently the standard of care for advanced human epidermal growth factor receptor 2(HER2)-positive gastric cancer.However,the emergence of resistance to trastuzumab poses significant challenges.AIM To identify the key genes associated with trastuzumab resistance.These results provide a basis for the development of interventions to address drug resistance and improve patient outcomes.METHODS High-throughput sequencing and bioinformatics were used to identify the differentially expressed pivotal gene BIRC3 and delineate its potential function and pathway regulation.Tumor samples were collected from patients with HER2-positive gastric cancer to evaluate the correlation between BIRC3 expression and trastuzumab resistance.We established gastric cancer cell lines with both highly expressed and suppressed levels of BIRC3,followed by comprehensive in vitro and in vivo experiments to confirm the involvement of BIRC3 in trastuzumab resistance and to elucidate its underlying mechanisms.RESULTS In patients with HER2-positive gastric cancer,there is a significant correlation between elevated BIRC3 expression in tumor tissues and higher T stage,tumor node metastasis stage,as well as poor overall survival and progressionfree survival.BIRC3 is highly expressed in trastuzumab-resistant gastric cancer cell lines,where it inhibits tumor cell apoptosis and enhances trastuzumab resistance by promoting the phosphorylation and activation of the phosphoinositide 3-kinase-Akt(PI3K-AKT)pathway in HER2-positive gastric cancer cells,both in vivo and in vitro.CONCLUSION This study revealed a robust association between high BIRC3 expression and an unfavorable prognosis in patients with HER2-positive gastric cancer.Thus,the high expression of BIRC3 stimulated PI3K-AKT phosphorylation and activation,stimulating the proliferation of HER2-positive tumor cells and suppressing apoptosis,ultimately leading to trastuzumab resistance.

Calcification-associated molecular traits and therapeutic strategies in hormone receptor-positive HER2-negative breast cancer

Objective:Mammographic calcifications are a common feature of breast cancer,but their molecular characteristics and treatment implications in hormone receptor-positive(HR+)/human epidermal growth factor receptor 2-negative(HER2−)breast cancer remain unclear.Methods:We retrospectively collected mammography records of an HR+/HER2−breast cancer cohort(n=316)with matched clinicopathological,genomic,transcriptomic,and metabolomic data.On the basis of mammographic images,we grouped tumors by calcification status into calcification-negative tumors,tumors with probably benign calcifications,tumors with calcification of lowmoderate suspicion for maligancy and tumors with calcification of high suspicion for maligancy.We then explored the molecular characteristics associated with each calcification status across multiple dimensions.Results:Among the different statuses,tumors with probably benign calcifications exhibited elevated hormone receptor immunohistochemical staining scores,estrogen receptor(ER)pathway activation,lipid metabolism,and sensitivity to endocrine therapy.Tumors with calcifications of high suspicion for malignancy had relatively larger tumor sizes,elevated lymph node metastasis incidence,Ki-67 staining scores,genomic instability,cell cycle pathway activation,and may benefit from cyclin-dependent kinase 4 and 6(CDK4/6)inhibitors.Conclusions:Our research established links between tumor calcifications and molecular features,thus proposing potential precision treatment strategies for HR+/HER2−breast cancer.

Inetetamab combined with tegafur as second-line treatment for human epidermal growth factor receptor-2-positive gastric cancer: A case report

BACKGROUND Human epidermal growth factor receptor-2(HER-2)plays a vital role in tumor cell proliferation and metastasis.However,the prognosis of HER2-positive gastric cancer is poor.Inetetamab,a novel anti-HER2 targeting drug independently developed in China,exhibits more potent antibody-dependent cell-mediated cytotoxicity than trastuzumab,which is administered as the first-line treatment for HER2-positive gastric cancer in combination with chemotherapy.In this case,the efficacy and safety of inetetamab combined with tegafur was investigated as a second-line treatment for HER2-positive gastric cancer.CASE SUMMARY A 52-year-old male patient with HER2-positive gastric cancer presented with abdominal distension,poor appetite,and fatigue two years after receiving six cycles of oxaliplatin combined with tegafur as first-line treatment after surgery,followed by tegafur monotherapy for six months.The patient was diagnosed with postoperative recurrence of gastric adenocarcinoma.He received 17 cycles of a combination of inetetamab,an innovative domestically developed anti-HER2 monoclonal antibody,and tegafur chemotherapy as the second-line treatment(inetetamab 200 mg on day 1,every 3 wk combined with tegafur twice daily on days 1–14,every 3 wk).Evaluation of the efficacy of the second-line treatment revealed that the patient achieved a stable condition and progression-free survival of 17 months.He tolerated the treatment well without exhibiting any grade 3-4 adverse events.CONCLUSION Inetetamab combined with chemotherapy for the treatment of metastatic HER2-positive gastric cancer demonstrates significant survival benefits and acceptable safety.