HER2‐positive patients receiving trastuzumab treatment have a comparable prognosis with HER2‐negative advanced gastric cancer patients: A prospective cohort observation

The monoclonal antibody trastuzumab has brought survival benefit to patients with advanced gastric cancer (AGC) that have human epidermal growth factor receptor 2 (HER2) over expression or amplification. This study was designed to compare the clinical outcomes of HER2‐negative and HER2‐positive AGC patients with or without trastuzumab treatment. There were three groups of patients enrolled for analysis. Group A was 51 HER2‐positive AGC patients treated with trastuzumab and chemotherapy; group B was a matched control group of 47 HER2‐positive patients who received chemotherapy only; group C was a matched group of 251 HER2‐negative patients who received chemotherapy. All the patients were enrolled at Sun Yat‐sen University Cancer Center or Zhongshan Hospital, Fudan University between January 2010 and December 2012. The primary endpoint was overall survival (OS). The Kaplan‐Meier method and log‐rank test were used for survival analysis. The median duration of follow‐up was 13.5 months (range 5–18.6 months). The median OS of these three groups of patients was 14.8 months, 11.3 months and 14.4 months respectively (p < 0.001). The survival difference between group A and B was significant, p < 0.001. Similarly, there was significant difference between group B and C, p < 0.001. Moreover the survival between group A and C was comparable, p = 0.281. The median progression‐free survival for these three groups was 7.4, 6.0 and 7.2 months. Multivariate analysis confirmed that trastuzumab treatment was an independent prognostic factor in group A and B patients (p = 0.017). HER2 positive was an independent adverse prognostic factor in group B and C patients (p = 0.013).     

Impact of clinicopathological characteristics on the efficacy of neoadjuvant therapy in patients with human epidermal growth factor receptor‐2‐positive breast cancer

Neoadjuvant therapy has become increasingly common in human epidermal growth factor receptor‐2 (HER2)‐positive breast cancer. In this study, we examined the impact of different clinicopathological characteristics on pathological complete response (pCR) in patients treated with anti‐HER2 agents. The PubMed and Embase databases were searched from inception through April 2017 to identify studies that met pre‐specified criteria. The odds ratios (ORs) and 95% confidence intervals (CIs) were extracted directly or were calculated with other available information. Eleven randomized controlled trials (RCTs) that involved 3,269 HER2‐positive women were included in this meta‐analysis. Patients with hormone receptor (HR)‐negative breast cancer benefited more from anti‐HER2 therapy than did patients with HR‐positive tumours (OR, 2.25; 95% CI, 1.93‐2.62). Furthermore, this improvement in pCR was independent of anti‐HER2 agents, phase, combined chemotherapy, neoadjuvant duration, year the trials started and region where the trials were conducted. Patients with small tumours achieved greater benefits than patients with large tumours (OR, 1.25; 95% CI, 1.00‐1.55). Age did not predict an additional benefit from anti‐HER2 neoadjuvant treatment (OR, 1.02; 95% CI, 0.73‐1.45). The impact of nodal status on pCR was dependent on the anti‐HER2 agents. In conclusion, for HER2‐targeted neoadjuvant treatment in breast cancer, greater benefits were achieved in patients with small HR‐negative tumours compared with patients with large HR‐positive tumours. These results may improve drug development and treatment strategies, economic analyses and the design and interpretation of clinical trials.     

Reduced PTEN expression in breast cancer cells confers susceptibility to inhibitors of the PI3 kinase/Akt pathway.

The PTEN protein is a lipid phosphatase with putative tumor suppressing abilities, including inhibition of the PI3K/Akt signaling pathway. Inactivating mutations or deletions of the PTEN gene, which result in hyper-activation of the PI3K/Akt signaling pathway, are increasingly being reported in human malignancies, including breast cancer, and have been related to features of poor prognosis and resistance to chemotherapy and hormone therapy. Prior studies in different tumor models have shown that, under conditions of PTEN deficiency, the PI3K/Akt signaling pathway becomes a fundamental proliferative and survival pathway, and that pharmacological inhibition of this pathway results in tumor growth inhibition. This study aimed to explore further this hypothesis in breast cancer cells. To this end, we have determined the growth response to inhibition of the PI3K/Akt signaling pathway in a series of breast cancer cell lines with different PTEN levels. The PTEN-negative cell line displayed greater sensitivity to the growth inhibitory effects of the PI3K inhibitor, LY294002 and rapamycin, an inhibitor of the PI3K/Akt downstream mediator mTOR, compared with the PTEN-positive cell lines. To determine whether or not these differences in response are specifically due to effects of PTEN, we developed a series of cell lines with reduced PTEN protein expression compared with the parental cell line. These reduced PTEN cells demonstrated an increased sensitivity to the anti-proliferative effects induced by LY294002 and rapamycin compared with the parental cells, which corresponded to alterations in cell cycle response. These findings indicate that inhibitors of mTOR, some of which are already in clinical development (CCI-779, an ester of rapamycin), have the potential to be effective in the treatment of breast cancer patients with PTEN-negative tumors and should be evaluated in this setting.     

Endocrine resistance associated with activated ErbB system in breast cancer cells is reversed by inhibiting MAPK or PI3K/Akt signaling pathways

Endocrine therapy resistance is one of the main challenges in the treatment of estrogen receptor positive (ER+) breast cancer patients. This study showed that two ER+ human breast carcinoma cell lines derived from MCF‐7 (MVLN cells) that have acquired under OH‐Tamoxifen selection two distinct phenotypes of endocrine resistance both displayed constitutive activation of the PI3K/Akt and MAPK pathways. Aberrant expression and activation of the ErbB system (phospho‐EGFR, phospho‐ErbB2, phospho‐ErbB3, over‐expression of ErbB4 and over‐expression of several ErbB ligands) were also observed in the two resistant cell lines, suggesting the existence of an autocrine loop leading to constitutive activation of MAPK and PI3K/Akt survival pathways. The recent clinical use of specific signal transduction inhibitors is one of the most promising therapeutic approaches in breast cancers. The MEK inhibitor PD98059 and the PI3K inhibitor LY294002 were both able to enhance the cytostatic effect of OH‐Tamoxifen or fulvestrant on MVLN sensitive cells. In the two resistant cell lines, inhibition of the MAPK or the PI3K/Akt pathways associated with endocrine therapy was sufficient to reverse OH‐Tamoxifen or fulvestrant resistance. Investigating the effect of a combination of both inhibitors on the reversion of OH‐Tamoxifen and fulvestrant resistance in the two resistant cell lines suggested that, in clinical practice, a strategy combining the two inhibitors would be the best approach to target the different endocrine resistance phenotypes possibly present in a tumor. In conclusion, the combination of MAPK and PI3K inhibitors represents a promising strategy to overcome endocrine therapy resistance in ER+ breast cancer patients.     

Current status of PI3K-mTOR inhibition in hormone-receptor positive,HER2-negative breast cancer

Breast cancer (BC) is the most common cancer in women and second only to lung cancer in terms of mortality. Among the three different BC subtypes, the oestrogen receptor positive represents nearly 70% of all cases and it is usually treated with anti-oestrogen drugs. However, the majority of hormone receptor positive metastatic BC patients develop resistance to anti-oestrogen treatments. The need for more down-stream therapies brought to the development of therapeutic strategies inhibiting the phosphatidylinositol 3-kinase-mammalian target of rapamycin (mTOR) pathway. Inhibitors of the mTOR have been tested in different clinical trials; everolimus has been Food and Drug Administration approved for the treatment of oestrogen receptor positive/human epidermal growth factor receptor 2 negative BC patients in combination with exemestane in patients who have progressed to anastrozole or letrozole after the encouraging results coming from BOLERO-2 trial. Similar results were obtained by the TAMRAD investigatory study testing tamoxifen in combination with everolimus in advanced BC. This editorial focuses on the results from BOLERO-2, BOLERO 4 and BOLERO-6, which tested the clinical importance of mTOR inhibition. We comment also on the role of phosphatidylinositol 3-kinase-mTOR inhibition as reported in the BELLE-2 and BELLE-3 trials and the future directions for the inhibition of this tumour metabolic axis.     

HER2阳性乳腺癌治疗模式的进展和优化

随着抗人表皮生长因子受体2（human epidermalgrowth factor receptor 2 ,HER2）抗肿瘤药物的不断出现及广泛应用,HER2 阳性乳腺癌患者的治疗以及预后得到了显著的改善。PEONY 研究结果的发布再次奠定了帕妥珠单抗+曲妥珠单抗的双靶治疗模式在新辅助治疗领域中的地位;结合TRYPHAENA 和TRAIN-2 两项研究,紫杉类+铂类应该是抗HER2 双靶治疗的首选化疗方案,疗程宜6 个周期。结合中国乳腺癌新辅助治疗专家共识和辅助APT 研究的最新随访结果,新辅助治疗适用人群为肿瘤直径超过3 cm 和/或淋巴结阳性的患者,新辅助治疗后如果没有获得pCR,T-DM1 应该是辅助治疗的首选模式,帕妥珠单抗+曲妥珠单抗的双靶辅助模式期待PEONY 研究的后续生存随访;对于没有淋巴结转移的小肿瘤（≤3 cm）低危患者可以考虑免除新辅助治疗,采取直接手术+术后给予曲妥珠单抗联合单药紫杉醇的辅助治疗模式。曲妥珠单抗+帕妥珠单抗联合紫杉类药物依然是晚期HER2 阳性患者的标准一线治疗;对于中国患者而言,吡咯替尼联合卡培他滨可以作为二线的优选;T-DM1 可以作为三线及后线选择;曲妥珠单抗、帕妥珠单抗、T-DM1 治疗失败的情况下,DS-8201 成为新的选择模式;伴有脑转移的HER2 阳性晚期乳腺癌患者则可以考虑图卡替尼与曲妥珠单抗和卡培他滨的联合治疗模式。     

人表皮生长因子受体-2及雌激素受体与乳腺癌的关系

乳腺癌与人表皮生长因子受体-2及雌激素受体关系密切,这两种受体也是乳腺癌的分类标准和治疗靶点。在大多数乳腺癌患者中,人表皮生长因子受体-2信号途径和雌激素受体信号途径参与了细胞的增生存活过程。而且在乳腺癌病例中,人表皮生长因子受体-2和雌激素受体呈现出一定程度的负相关。这说明这两种受体活化后有一些联系。本文简要综述了人表皮生长因子受体-2和雌激素受体的联系以及这种联系在乳腺癌治疗中的意义。     

Dual targeted therapy with pyrotinib and trastuzumab for HER2‐positive advanced colorectal cancer: A phase 2 trial

This trial was initiated to evaluate the efficacy and safety of pyrotinib in combination with trastuzumab in patients with human epidermal growth factor receptor 2 (HER2)‐positive recurrent/metastatic colorectal cancer (CRC). In this single‐arm, open‐label, multicenter, phase 2 trial patients with HER2‐positive recurrent/metastatic CRC were enrolled and received oral pyrotinib 400 mg once a day plus intravenous trastuzumab 8 mg/kg loading dose followed by 6 mg/kg once every 3 weeks. The primary endpoint was the objective response rate (ORR). Disease control rate (DCR), progression‐free survival (PFS), duration of response, and safety were assessed as secondary endpoints. From December 2019 to October 2021, a total of 20 patients were enrolled and 18 of them were evaluable for response. All patients were B‐rapidly accelerated fibrosarcoma (BRAF) wild type. Four patients achieved partial response, with an ORR of 22.2% (4/18, 95% confidence interval [CI] 6.4–47.6) and DCR of 61.1% (11/18, 95% CI 35.8–82.7), while the ORR and DCR were 33.3% (4/12, 95% CI 13.8–60.9) and 83.3% (10/12, 95% CI 51.6–97.9), respectively, in RAS wild‐type patients. At the time of cut‐off day, median follow‐up was 10.7 months (range 3.8–13.8). The median PFS was 3.4 months (95% CI 1.8–4.3) in the overall population and 4.3 months (95% CI 3.2–8.5) in the RAS wild‐type group. The most common adverse event of grade ≥3 was diarrhea (13/20, 65.0%). Pyrotinib combined with trastuzumab showed promising antitumor activity and a manageable safety profile in patients with RAS/BRAF wild‐type HER2‐positive advanced CRC.     

Correlation of p27 protein expression with HER-2/neu expression in breast cancer

Strong expression of human epidermal growth factor receptor 2 (HER-2)/neu in breast cancer has been associated with poor prognosis. Reduced expression of p27(Kip1), a cyclin-dependent kinase inhibitor, correlates with poor clinical outcome in breast cancer. In this study, we provide a correlation between these two important prognostic markers in patients with breast cancer. Breast tumor screening using immunohistochemistry indicated that downregulation of p27 correlated with HER-2/neu overexpression in studying 11 normal breast tissues and 51 primary breast carcinomas. We found HER-2/neu protein overexpression in 20 (41%) of 49 breast cancers and low p27 protein expression in 47 (92%) of 51 breast cancers. All 20 (100%) of the tumors that overexpressed HER-2/neu had low levels of p27 protein product; this correlation was statistically significant (P = 0.035). Decreasing p27 expression correlated with increasing HER-2/neu activity. Our results suggest that one function of the HER-2/neu product is to downregulate p27 expression in breast cancer. This study may be significant in selecting patients for HER-2/neu antibody therapy in the future. Mol. Carcinog. 30:169--175, 2001.     

雌激素受体β和人类表皮生长因子受体2在乳腺癌中的表达及其临床意义

我们应用免疫组化两步法,对133例乳腺癌和29例乳腺良性病变的标本进行雌激素受体(estrogen receptor,ER)β、ERα和人类表皮生长因子受体(human epidermal growth factor receptor,HER)2表达的测定,比较了ERβ在临床病理指标各组中的阳性表达差异,并探讨ERβ与HER 2和ERα的关系。     

229例人表皮生长因子受体2阳性Ⅳ期乳腺癌患者曲妥珠单抗的治疗分析

目的 探讨曲妥珠单抗对人表皮生长因子受体2(HER2)阳性Ⅳ期乳腺癌的治疗效果及患者预后的影响因素.方法 收集229例应用曲妥珠单抗治疗的HER2阳性Ⅳ期乳腺癌患者的临床资料,采用Cox比例风险回归模型分析HER2阳性Ⅳ期乳腺癌患者无进展生存时间(PFS)和总生存时间(OS)的影响因素.结果 229例HER2阳性Ⅳ期乳...     

曲妥珠单抗耐药后HER 2阳性转移性乳腺癌靶向治疗策略

人表皮生长因子受体2（human epidermal growth factor receptor 2,HER 2）是一种跨膜酪氨酸激酶受体,可以激活下游一系列信号通路,导致肿瘤细胞增殖和存活。HER 2阳性乳腺癌是乳腺癌的特殊类型,恶性程度高,预后差。抗HER 2单克隆抗体曲妥珠单抗能够改善该类乳腺癌治疗效果,但最终仍难逃耐药的结局。近年来,针对曲妥珠单抗耐药机制的研究、新型靶向药物的研发以及治疗策略的探索,在克服曲妥珠单抗耐药性方面取得了重大进展,本文将对其耐药后治疗策略及临床试验数据进行综述。     

Escalating and de-escalating treatment in HER2-positive early breast cancer

The current standard adjuvant systemic treatment of early HER2-positive breast cancer consists of chemotherapy plus 12 months of trastuzumab, with or without endocrine therapy. Several trials have investigated modifications of the standard treatment that are shorter and less resource-demanding (de-escalation) or regimens that aim at dual HER2 inhibition or include longer than 12 months of HER2-targeted treatment (escalation). Seven randomized trials investigate shorter than 12 months of trastuzumab treatment duration. The shorter durations were not statistically inferior to the 1-year duration in the 3 trials with survival results available, but 2 of the trials were small and 1 had a relatively short follow-up time of the patients at the time of reporting. The pathological complete response (pCR) rates were numerically higher in all 9 randomized trials that compared chemotherapy plus dual HER2 inhibition consisting of trastuzumab plus either lapatinib, neratinib, or pertuzumab with chemotherapy plus trastuzumab as neoadjuvant treatments, but the superiority of chemotherapy plus dual HER2-inhibition over chemotherapy plus trastuzumab remains to be demonstrated in the adjuvant setting. One year of adjuvant trastuzumab was as effective as 2 years of trastuzumab in the HERA trial, and was associated with fewer side-effects. Extending 1-year adjuvant trastuzumab treatment with 1 year of neratinib improved disease-free survival in the ExteNET trial, but the patient follow-up times are still short, and no overall survival benefit was reported. Several important trials are expected to report results in the near future and may modify the current standard.