Pyrotinib-based therapeutic approaches for HER2-positive breast cancer: the time is now

Real-World Outcomes of Pyrotinib-Based Therapy for HER2-Positive Breast Cancer With Brain Metastases: A Multicentre, Retrospective Analysis

OBJECTIVE

This study was designed to investigate the efficacy and safety of pyrotinib-based therapy for HER2-positive breast cancer with brain metastases (BM) in the real-world setting.

METHODS

Data of HER2-positive breast cancer patients with BM treated with pyrotinib-based therapy from a multicetre, registered, real-world study were analyzed.

RESULTS

Among 45 female patients, the overall objective response rate (ORR) was 62.2%, higher in 1st/2nd-line than ≥ 3rd-line (71.0% vs. 42.9%, P = .072). The objective response rate of intracranial lesions (CNS-ORR) was 71.1 %, with a significantly higher CNS-ORR observed in the 1st or 2nd-line subgroup compared to that of ≥ 3rd-line subgroup (83.9% vs. 42.9%, P < .05). By the end of follow-up, 20 patients (44.4%) died, and the 1-year survival rate was 73.3%. The median progression-free survival (PFS) was 9.1 months (95% CI 6.7-11.5). Patients with 1 or 2 BM had a longer median PFS of 12.0 months compared to 7.7 months for those with ≥ 3 BM (P = .01). In addition, 1- or 2-line therapy and full dose exposure of pyrotinib of 320mg-400mg/day were associated with improved median PFS (all P > .05). The median intracranial PFS (CNS-PFS) was 11.4 months (95% CI 7.5-15.3). However, local intervention plus systemic treatment seemed to prolong CNS-PFS compared with systemic treatment alone (13.7 vs. 9.1 months, P = .128). Diarrhea was most common (88.9%), 24.4% grade 3.

CONCLUSIONS

The pyrotinib-based therapy is effective for HER-2 positive breast cancer with BM, especially in 1st- or 2nd-line treatment, with tolerable adverse events. However, insufficient dosing of pyrotinib may impair efficacy outcomes.

Impact of METTL3/14/16 Gene Polymorphisms on Risk of Breast Cancer in Chinese Women

OBJECTIVES

Methyltransferase-like 3/14/16 (METTL3/14/16) presents the regulating valve in N6-methyladenosine (m6A) modification, involved in carcinogenesis. We addressed elucidating the relationship between single-nucleotide polymorphisms (SNPs) of the METTL3/14/16 gene and breast cancer (BC) susceptibility.

STUDY DESIGN

A case-control study included 680 BC patients and 680 healthy controls, individually matched for age (±2 years).

METHODS

7 SNPs were screened by bioinformatics tools. Conditional Logistic analysis was used to explore the association between SNPs and BC susceptibility. SNPs-reproductive factors interaction was assessed. qRT-PCR was conducted to detect the METTL3/14/16 expression of different SNPs. The potential biomechanism was explored using bioinformatics tools.

RESULTS

Among the 7 analyzed SNPs, METTL3 rs1061026 T>G exhibited a significant association with reduced susceptibility to BC. The TC+CC genotype of METTL14 rs428409 elevated BC risk, while the AG+GG genotype of METTL14 rs3087958 restrained BC risk. The stratified analysis further identified the protective effect of rs1061026 T>G and rs3087958 T>G, and the detrimental effect of rs428409 T>G in specific subgroups. Haplotype analysis revealed that haplotypes Grs1061026Crs1061027 and Grs368669Trs428409Grs3087958 were protective for BC. BC patients who carried the C allele in METTL14 rs428409 were more likely to be HER-2 positive. Individuals with age at menarche ≥14, number of pregnancies >1, and G allele in rs1061026 had a 47.7% decreased risk of BC. There were considerable multiplicative interactions between SNPs and reproductive factors. The relative expression of METTL3/14 was altered due to rs1061026 T>G, rs428409 T>C, and rs3087958 A>G. These three SNPs might interfere with the m6A modification and the expression level of BC-related genes.

CONCLUSION

Our findings suggested that rs1061026 T>G, rs428409 T>C, and rs3087958 A>G might be associated with the risk of BC.

Comparative efficacy and safety of pyrotinib plus trastuzumab versus trastuzumab plus pertuzumab and trastuzumab monotherapy in neoadjuvant treatment of HER2-positive breast cancer: A systematic review and meta-analysis

INTRODUCTION

HER2-positive breast cancer is an aggressive subtype that benefits from targeted therapies. Some studies have shown that pyrotinib (P) plus trastuzumab (H) has a good efficacy against early or locally advanced HER2-positive breast cancer. However, there is still no systematic review and meta-analysis supporting the efficacy and safety of pyrotinib plus trastuzumab versus standard regimens in the neoadjuvant treatment of early or locally advanced breast cancer. This study is the first systematic review and meta-analysis to compare the efficacy and safety of pyrotinib combined with trastuzumab versus trastuzumab combined with pertuzumab (Per) and trastuzumab monotherapy in the neoadjuvant treatment of HER2-positive breast cancer.

METHODS

We conducted a systematic literature search in PubMed, Embase, the Cochrane Library, CNKI, Wan Fang and VIP databases for relevant studies published up to August 30th, 2024. RCTs, cohort studies and retrospective studies with HER2-positive breast cancer patients who had not received breast cancer-related treatments previously were included. Treatment of P + H, H or Per + H arms with chemotherapy combined with pyrotinib plus trastuzumab, trastuzumab or pertuzumab plus trastuzumab as neoadjuvant treatment. The primary outcome was the total pathological complete response (tpCR), and secondary outcomes included breast pathological complete response (bpCR), ORR, DCR, and grade III/IV AEs. The quality of evidence was assessed using the GRADE.

RESULTS

A total of nine studies (4 RCTs, 1 prospective cohort study and 4 retrospective analysis) involving 1745 patients were included. The P + H arm showed no significant difference in tpCR compared to Per + H (RR: 0.94, 95 % CI: 0.80-1.11, p = 0.46) but demonstrated a significant improvement in tpCR over trastuzumab monotherapy (RR: 1.83, 95 % CI: 1.56-2.15, p < 0.001). This finding was further confirmed in meta-analysis of RCTs (RR: 1.87, 95 % CI: 1.42-2.47, p < 0.001). The P + H arm had a higher incidence of grade III/IV diarrhea (RR: 10.54, 95 % CI: 5.96-18.63, p < 0.001) but similar rates of other AEs compared to the H arm. The evidence quality for tpCR (P + H vs. H, RCT) was high, and that for tpCR (P + H vs. H) was moderate, while that for tpCR (P + H vs. Per + H) was low.

CONCLUSIONS

Pyrotinib combined with trastuzumab may offer an effective neoadjuvant treatment option for HER2-positive breast cancer, with a superior efficacy over trastuzumab alone. However, pyrotinib plus trastuzumab did not show better efficacy compared with Per + H. Pyrotinib plus trastuzumab was associated with more diarrhrea than trastuzumab monotherapy. In addition, P + H is less cost-effective compared with the combination of Per + H.

Disitamab vedotin combined with pyrotinib as salvage treatment in Her-2-amplified treatment refractory metastatic colorectal cancer: a case report

Background

Human epidermal growth factor receptor 2 (HER-2) amplification has been identified in approximately 3% of patients with metastatic colorectal cancer (mCRC). Owing to the lack of established anti-ERBB2 therapeutic approaches, mCRC patients with Her-2 amplification rarely receive targeted treatments. Moreover, conventional chemotherapy regimens are not ideal for these patients, leaving options in the advanced stage limited to best supportive care or participation in clinical drug trials.

Case presentation

This report presents a case of a patient with Her-2-amplified refractory mCRC treated with a salvage regimen combining Disitamab Vedotin and Pyrotinib, resulting in a partial response and progression-free survival for 6 months, which is still ongoing.

Conclusion

This case study suggests that the anti-Her-2 regimen involving Disitamab Vedotin and Pyrotinib may offer a potential salvage treatment option for patients with Her-2-amplified mCRC patients. However, further validation in larger cohorts is necessary in future studies.

Development of a risk prediction nomogram model of pyrotinib-induced severe diarrhea

BACKGROUND

To identify the factors influencing pyrotinib-induced severe diarrhea and to establish a risk prediction nomogram model.

METHODS

The clinical data of 226 patients received pyrotinib from two medical institutions from January 2019 to December 2023 were analysed retrospectively. A training set was made up of 167 patients from Hainan Cancer Hospital, and the external validation set was made up of 59 patients from Hainan West Central Hospital. Univariate and multivariate logistic regression analysis were used to identify independent factors influencing pyrotinib-induced severe diarrhea, and a risk prediction nomogram model was constructed, which was verified on patients in the external validation set.

RESULTS

History of adverse reactions (ADRs), initial dose of pyrotinib, combination with capecitabine, thrombocytopenia, aspartate transaminase (AST), and use of probiotics or other drugs that regulate the gut microbiota were identified as independent influencing factors for pyrotinib-induced severe diarrhea (all P < 0.05). Based on these, a risk prediction nomogram model of pyrotinib-induced severe diarrhea was established. The area under the receiver operating characteristic curve was 0.794 and 0.863 in the training set and the external validation set, respectively. The calibration curve of the prediction model displayed good consistency both the two sets, which indicated that the model could have favourable predictive ability.

CONCLUSION

The risk prediction nomogram model of pyrotinib-induced severe diarrhea constructed in this study may identify high risk populations earlier so that clinicians can make appropriate decisions in time.

TTK promotes HER2 + breast cancer cell migration, apoptosis, and resistance to targeted therapy by modulating the Akt/mTOR axis

BACKGROUND

HER2 + breast cancer is a malignant neoplasm with a high degree of aggressiveness and therapeutic challenge. In recent years, studies have indicated a strong correlation between TTK and various tumors, though its role in HER2 + BRCA remains unclear.

OBJECTIVES

Studying the biological function of the TTK gene in HER2 + BRCA and its resistance to targeted therapy it provides new ideas for targeted drug research.

METHODS

TTK was knocked down by small interfering RNA transfection, and its biological function in HER2 + BRCA cells was verified, and its mechanism of action was verified by RT-PCR and Western blot.

RESULTS

The study demonstrated that TTK promoted cell proliferation and migration by activating the Akt/mTOR pathway in HER2 + breast cancer and enhanced the drug sensitivity of BRCA cell lines SKBR3 and BT474 to pyrotinib, in addition, knockdown of TTK induced apoptosis and arrested cells in G1 phase.

CONCLUSION

Which implies that TTK is an oncogene in HER2 + BRCA and is a valuable research target.

Efficacy and Safety of Neoadjuvant Pyrotinib for Human Epidermal Receptor 2-Positive Breast Cancer: A Meta-Analysis

Neoadjuvant pyrotinib shows the potential to improve treatment response in human epidermal receptor 2 (HER2)-positive breast cancer patients, but relevant meta-analyses are scarce. This meta-analysis intended to explore the efficacy and safety of neoadjuvant pyrotinib for HER2-positive breast cancer patients. Studies comparing the efficacy and safety between HER2-positive breast cancer patients receiving pyrotinib-containing neoadjuvant treatment (pyrotinib group) and those receiving other neoadjuvant treatments (control group), were searched in EMBASE, Web of Science, Cochrane, PubMed, China National Knowledge Infrastructure, Wanfang, and SinoMed until December 2023. Six randomized controlled trials (RCTs) and 4 cohort studies were included. The pyrotinib group and control group contained 540 and 684 patients, respectively. Pathological complete response (pCR) was higher in the pyrotinib group than in the control group [relative risk (RR)=1.93; 95% confidence interval (CI) = 1.63-2.29; P < 0.001]. Similar results were discovered in subgroup analyses of RCTs (RR = 1.89; 95% CI = 1.49-2.40; P < 0.001) and cohort studies (RR = 1.98; 95% CI = 1.55-2.53; P < 0.001). The objective response rate (ORR) was also higher in the pyrotinib group than in the control group (RR = 1.14; 95% CI = 1.07-1.21; P < 0.001). Regarding adverse events, only the incidence of diarrhea was increased in the pyrotinib group versus the control group (RR = 1.97; 95% CI = 1.31-2.96; P = 0.001), while others were not different, including nausea and vomiting, leukopenia, thrombocytopenia, hand-foot syndrome, and alopecia (all P > 0.05). No publication bias existed, and sensitivity analysis suggested the satisfactory robustness of this meta-analysis. In conclusion, compared with other neoadjuvant treatments, pyrotinib-containing neoadjuvant treatment achieves a better treatment response with a good safety profile in HER2-positive breast cancer patients.

Overcoming brain-derived therapeutic resistance in HER2+ breast cancer brain metastasis

Brain metastasis of HER2+ breast cancer occurs in about 50% of all women with metastatic HER2+ breast cancer and confers poor prognosis for patients. Despite effective HER2-targeted treatments of peripheral HER2+ breast cancer with Trastuzumab +/-HER2 inhibitors, limited brain permeability renders these treatments inefficient for HER2+ breast cancer brain metastasis (BCBM). The scarcity of suitable patient-derived in-vivo models for HER2+ BCBM has compromised the study of molecular mechanisms that promote growth and therapeutic resistance in brain metastasis. We have generated and characterized new HER2+ BCBM cells (BCBM94) isolated from a patient HER2+ brain metastasis. Repeated hematogenic xenografting of BCBM94 consistently generated BCBM in mice. The clinically used receptor tyrosine kinase inhibitor (RTKi) Lapatinib blocked phosphorylation of all ErbB1-4 receptors and induced the intrinsic apoptosis pathway in BCBM94. Neuregulin-1 (NRG1), a ligand for ErbB3 and ErbB4 that is abundantly expressed in the brain, was able to rescue Lapatinib-induced apoptosis and clonogenic ability in BCBM94 and in HER2+ BT474. ErbB3 was essential to mediate the NRG1-induced survival pathway that involved PI3K-AKT signalling and the phosphorylation of BAD at serine 136 to prevent apoptosis. High throughput RTKi screening identified the brain penetrable Poziotinib as highly potent compound to reduce cell viability in HER2+ BCBM in the presence of NRG1. Successful in-vivo ablation of BCBM94- and BT474-derived HER2+ brain tumors was achieved upon two weeks of treatment with Poziotinib. MRI revealed BCBM remission upon poziotinib, but not with Lapatinib treatment. In conclusion, we have established a new patient-derived HER2+ BCBM in-vivo model and identified Poziotinib as highly efficacious RTKi with excellent brain penetrability that abrogated HER2+ BCBM brain tumors in our mouse models.