Preventive effect of dexamethasone premedication on the development of infusion-related reaction in breast cancer patients receiving trastuzumab.

AIM: To clarify the incidence and risk factors of infusion-related reactions (IRRs) caused by trastuzumab in breast cancer patients and verify the preventive effects of dexamethasone. METHODS: All breast cancer patients newly treated with trastuzumab at the Osaka Medical and Pharmaceutical University Hospital from 1 January 2017 to 31 December 2020 were included. The electronic medical records were retrospectively reviewed. The outcome measure was the occurrence of IRRs of grade 1 or higher during trastuzumab infusion. Only dexamethasone and anticancer drugs administered concomitantly before trastuzumab were used as explanatory variables. RESULTS: The 176 patients included in the study received 2320 infusions. Fifty-eight patients (33.0%) experienced IRRs, and IRRs occurred in 80 (3.4%) of the total 2320 infusions. Owing to the hierarchical structure of the data, the independence of the observed values was evaluated using the intraclass correlation coefficient. Multivariate multilevel logistic regression analysis showed that premedication with dexamethasone lowered the risk of trastuzumab-induced IRRs (mg, per 1 unit, odds ratio [OR] = 0.61, 95% confidence interval [95% CI] 0.43-0.85, P = .003). In addition, preoperative status (OR = 38.9, 95% CI 5.4-278.7, P < .001) and high-dose trastuzumab (mg/kg, per 1 unit, OR = 60.6, 95% CI 20.1-182.9, P < .001) were independent risk factors for IRRs. CONCLUSION: The results of this study suggest that premedication with dexamethasone exhibits preventive effects on trastuzumab-induced IRRs in breast cancer patients. Future studies are needed to determine the optimal dose of dexamethasone to prevent IRRs and the impact of dexamethasone on the efficacy of trastuzumab in breast cancer.

[Updated CAP guidelines for determining molecular biological subtypes of breast cancer]. / Obnovlennye rekomendatsii CAP po opredeleniyu molekulyarno-biologicheskikh podtipov raka molochnoi zhelezy.

Updated 2023 guidelines from the College of American Pathologists (CAP) on immunohistochemical detection of human epidermal growth factor receptor type 2 (HER2), receptors of estrogen (ER) and progesterone (PgR), and the cell proliferation marker Ki-67 in breast cancer are presented. Attention is drawn to the emergence of two new terms «ER Low Positive¼ and «HER2 Low¼ to characterize tumors with low expression of estrogen receptors and HER2.

HER2-Positive Breast Cancer: Association of MRI and Clinicopathologic Features With Tumor-Infiltrating Lymphocytes.

BACKGROUND. Tumor-infiltrating lymphocytes (TILs) are associated with therapeutic outcomes and prognosis in patients with human epidermal growth factor receptor type 2 (HER2)-positive breast cancer. Identification of TIL levels is clinically relevant. OBJECTIVE. The purpose of our study was to explore associations of clinicopathologic and MRI features with TIL levels in patients with HER2-positive breast cancer. METHODS. A total of 212 consecutive women (mean age, 54.0 years) diagnosed with HER2-positive breast cancer between January 2017 and December 2019 were included in this retrospective study. Patients were divided into low-TIL (< 10%) and high-TIL (≥ 10%) groups. Three breast radiologists independently reviewed images; interreader agreement was assessed, and the first reader's findings were used for further analysis. Associations of clinicopathologic and MRI features with TIL levels were evaluated using multivariable logistic regression analysis. Subanalysis of TIL levels by hormone receptor (HR) status was also performed. RESULTS. A total of 115 (54.2%) patients had low TIL levels, and 97 (45.8%) patients had high TIL levels. A high TIL level was associated (all, p < .05) with histologic grade 3 (odds ratio [OR] = 3.98; frequency, 78.4% vs 52.2% in high- vs low-TIL groups, respectively), high tumor cellularity (OR = 4.59; median cellularity, 60% vs 50%), lower frequency of associated ductal carcinoma in situ (OR = 0.16; frequency, 86.6% vs 94.8%), and higher frequency of peritumoral edema on T2-weighted images (OR = 2.83; 71.1% vs 50.4%). In subgroup analysis by HR status, histologic grade 3 (OR = 5.03, p = .002) was a significant independent predictor of high TIL level in the HR-positive/HER2-positive group, whereas high tumor cellularity (OR = 9.06, p = .002), peritumoral edema (OR = 5.23, p = .03), and low ADC (OR = 11.69, p = .047) were independent predictors of high TIL level in the HR-negative/HER2-positive group. Interreader agreement for peritumoral edema was moderate among the three radiologists (к = 0.432-0.539). CONCLUSION. Peritumoral edema on MRI and the histopathologic feature of tumor aggressiveness help predict high TIL levels in patients with HER2-positive breast cancer. CLINICAL IMPACT. Pretreatment MRI features may serve as a useful tool for assessing TIL levels in patients with HER2-positive breast cancer and for helping to classify patients with variable clinical outcomes related to immune activity and to guide selection among neoadjuvant chemotherapy or HER2-targeted therapy or immunotherapy.

Replication Study for the Association of Five SNPs Identified by GWAS and Trastuzumab-Induced Cardiotoxicity in Japanese and Singaporean Cohorts.

Trastuzumab (herceptin) is an effective drug for human epidermal growth factor receptor type 2 (HER2)-positive cancer. However, cardiotoxicity remains a serious complication. In our previous genome-wide association study (GWAS), we identified potential associations for five single nucleotide polymorphisms (SNPs) with trastuzumab-induced cardiotoxicity in a Japanese population. To validate this association, here we performed replication studies using Japanese and Singaporean case-control cohorts (Japan: 6 cases and 206 controls; Singapore: 22 cases and 178 controls). Although none of the SNPs showed a statistically significant association with trastuzumab-induced cardiotoxicity, we show that three (rs8032978, rs7406710 and rs9316695) and four (rs8032978, rs7406710, rs28415722 and rs11932853) SNPs had an effect in the same direction in the Japanese and the Singaporean cohort, respectively, as that in our previous study. Combining the previous study with the current replication studies, we find a strong association for two SNPs, rs8032978 and rs7406710, with trastuzumab-induced cardiotoxicity (Pcombined = 4.92 × 10-5 and 5.50 × 10-5, respectively). These data suggest that rs8032978 and rs7406710 could be predictive markers of trastuzumab-induced cardiotoxicity in Japanese and Singaporean populations, and support their potential use in clinical risk assessment. These findings offer a first step toward the development of clinically available markers for the potential risk of trastuzumab-induced cardiotoxicity as well as an improved understanding of the pathogenesis of this complication.

Differences in expression of the cancer stem cell marker aldehyde dehydrogenase 1 among estrogen receptor-positive/human epidermal growth factor receptor type 2-negative breast cancer cases with early, late, and no recurrence.

BACKGROUND: The significance of the expression of aldehyde dehydrogenase 1 (ALDH1), a cancer stem cell marker, for predicting the recurrence of estrogen receptor (ER)-positive/human epidermal growth factor receptor type 2 (HER2)-negative breast cancer is still poorly understood. The value of ALDH1 in predicting the time of recurrence remains unknown. METHODS: In total, 184 patients with early distant recurrence, 134 patients with late distant recurrence, and 321 control patients without recurrence for more than 10 years after starting initial treatment for ER-positive/HER2-negative breast cancer, registered in 9 institutions, were analyzed. We assessed relationships between ALDH1 and other clinicopathological features, and ALDH1 expression was compared among the three groups. The relationship between ALDH1 expression and overall survival after recurrence was also evaluated in each group. RESULTS: The rates of ALDH1 expression positivity (more than 1 %) in the early, late, and no recurrence groups were 18.4 %, 13.4 %, and 8.4 %, respectively. ALDH1 expression correlated significantly with lymph node metastases (p = 0.048) and the Ki-67 labeling index (p < 0.001) in the early recurrence group. Multivariate analysis revealed ALDH1 expression to be significantly higher in the early recurrence group than in the no recurrence group (adjusted OR 2.140, 95 % CI 1.144-4.003, p = 0.016). Moreover, there was a significant difference in ALDH1 expression between the early and no recurrence groups receiving adjuvant endocrine therapy and chemotherapy (adjusted OR 4.625, 95 % CI 1.881-12.474, p < 0.001). However, there was no difference in ALDH1 expression between the late and no recurrence groups in univariate analysis (OR 1.507, 95 % CI 0.738-2.998, p = 0.253). In multivariate analysis, ALDH1 was not a factor independently predicting overall survival after the detection of recurrence (adjusted OR 1.451, 95 % CI 0.985-2.085, p = 0.059). CONCLUSIONS: Among patients with ER-positive/HER2-negative breast cancer, ALDH1 expression was more common in those with early recurrence, and this expression was found to be associated with a more aggressive breast cancer phenotype than that in the patients without recurrence. Further study is needed to clarify the prognostic significance of the heterogeneity of cancer stem cells and to confirm their role in resistance to chemotherapy.

Expansive hematoma in delayed cerebral radiation necrosis in patients treated with T-DM1: a report of two cases.

BACKGROUND: Multiple new targeted agents have been developed for patients with human epidermal growth factor receptor type 2 (HER2) - positive breast cancer. Patients with HER2- positive breast cancer will develop brain metastases with greater incidence than patients with non-HER2 cancers, and many of them will undergo stereotactic radiosurgery (SRS) or other CNS radiotherapy. The interaction between radiation effects and new targeted agents is not well understood. We report two cases suggesting a novel adverse effect of T-DM1 (trastuzumab emtansine) on symptomatic enlargement of radiation necrosis (RN) after SRS. CASE PRESENTATION: Two patients with HER2-positive breast cancer had received SRS for single brain metastasis more than 5-years ago. They had been heavily treated for HER2-positive metastatic breast cancer (trastuzumab and pacritaxel, lapatinib and capecitabine). They initiated T-DM1 therapy for progressive systematic disease 5.5 years after stereotactic irradiation, when a small RN was recognized on brain MR images of each patient. The RN lesions increased in size and became symptomatic during 13 or 14 months of T-DM1 treatment. The patients underwent surgical resection of the lesion. Pathological examination revealed necrosis, hematoma, granulation tissue and telangiectasia without neoplastic cells. CONCLUSIONS: A potential enhancement of RN by T-DM1 in the brain may be one of important adverse events associated with the use of T-DM1 for patients after SRS. These cases highlight the need of careful follow-up when combining new systemic targeted therapies and SRS for brain metastases.

Increasing survivors of anthracycline-related cardiomyopathy with breast cancer in trastuzumab era: thirty-one-year trends in a Japanese Community.

BACKGROUND: Trastuzumab has improved breast cancer (BC) prognosis and reduced anthracycline use. However, the characteristic changes of anthracycline-related cardiomyopathy (ARCM) in patients with BC remain unclear. We aimed to update our understanding of ARCM in the trastuzumab era. METHODS: This retrospective observational cohort study included 2959 patients with BC treated with anthracyclines at three regional cancer centers in Niigata City between 1990 and 2020. Seventy-five patients (2.5%) developed ARCM and were categorized into two groups: pre- 2007 (early phase) and post-2007 (late phase), corresponding to before and during the trastuzumab era in Japan. RESULTS: ARCM incidence peaked at 6% in the 1990s, then decreased and stabilized at 2% until the 2010s. Survivors of anthracycline-treated BC increased more rapidly in the late phase, with four times as many patients with ARCM compared to the end of the early phase (26 and six, respectively). Although the rate of change in accumulation from the early phase to the late phase was slight in the anthracycline-treated BC group, it was more pronounced in the ARCM group (P < 0.001). Mean anthracycline use in the late phase was significantly lower than in the early phase (307 vs. 525 mg/m2, P < 0.001). Five-year survival rates in the late phase tended to be higher than early phase (45% and 28%, respectively. P = 0.058). Human epidermal growth factor receptor type 2 (HER2) positivity with trastuzumab therapy in the late phase was an independent predictor for mortality within 10 years (hazard ratio = 0.24, 95% confidence interval: 0.10-0.56; P = 0.001). CONCLUSIONS: HER2-positive patients with ARCM receiving trastuzumab therapy had a better prognosis than HER2-positive and HER2-negative patients with ARCM not receiving trastuzumab therapy, and this trend has been increasing in the trastuzumab era. These findings highlight the importance of HER2-targeted treatments in improving prognosis for BC patients with ARCM.

Anti-tumour effects of lapatinib on HER2-positive canine prostatic carcinoma cell lines.

Background: Canine prostatic carcinoma (cPC) is a urogenital tumour with a poor prognosis, for which no effective treatment has been established. Recently, it has been shown that human epidermal growth factor receptor type 2 (HER2) is overexpressed in cPC cells; however, the efficacy of HER2-targeted therapy remains unclear. Aim: Investigate the anti-tumour effect of lapatinib on HER2-positive cPC cell lines. Methods: Two cell lines (muPC and bePC) were established from two dogs with cPC and the effects of lapatinib treatment on cell proliferation, apoptosis, and HER2 downstream signalling were investigated. Furthermore, muPC was used to generate tumour-bearing mice, and the anti-tumour effects of lapatinib were examined in vivo. Results: Lapatinib treatment inhibited the proliferation and phosphorylation of Erk1/2 and Akt, which are downstream signals of HER2. Furthermore, the TUNEL assay showed that lapatinib induced apoptosis in both cell lines. The muPC-engrafted nude mouse model showed that lapatinib significantly inhibited tumour growth and increased the area of necrotic tumour tissue compared to the vehicle-treated groups. Conclusion: Lapatinib exerts anti-tumour effects on cPC cells by inhibiting HER-2 signalling.

Efficacy and Safety of Radiotherapy Combined with Pyrotinib in the Treatment of HER2-Positive Breast Cancer with Brain Metastases.

Purpose: To explore the efficacy and safety of pyrotinib combined with different radiotherapy modes in human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC) patients with brain metastasis (BM). Patients and Methods: This study is a retrospective analysis of patients diagnosed with BM who underwent treatment with pyrotinib between November 2018 and April 2023. A total of 66 patients were administered radiotherapy in conjunction with pyrotinib (Group A), while 26 patients received pyrotinib as a standalone treatment (Group B). Within Group A, 18 patients underwent conventional fractionated radiotherapy (2Gy/F), while 48 patients received hyperfractionated radiotherapy (HFRT) (≥3Gy/F). The primary endpoints were intracranial progression-free survival (IC-PFS) and overall survival (OS). The secondary endpoints were objective response rate (ORR) and clinical benefit rate (CBR). Results: The ORR of Group A was 54.5% (36/66), while the ORR of Group B was 34.6% (9/26) (P= 0.047). The CBR of Group A was 89.4% (59/66) and that of Group B was 69.2% (18/26) (P= 0.041). The IC-PFS between Group A and Group B were 12 months and 8 months, respectively (P< 0.001), and the OS were 20 months and 16 months, respectively (P= 0.065). In Group A, the IC-PFS and OS between the conventional fractionation radiotherapy group and the HFRT group were 10 months and 12 months, respectively (P= 0.001) and 16 months and 24 months, respectively (P< 0.001). No serious adverse reactions were observed in Group A and Group B. Conclusion: For HER2-positive BC patients with BM, it is recommended to adopt the treatment mode of HFRT combined with pyrotinib, which can improve the local control and survival of patients.

Efficacy and safety of pyrotinib and radiotherapy vs. pyrotinib-based therapy in patients with HER2+ breast cancer with brain metastasis: a retrospective cohort study.

Background: At present, local therapy, such as surgery and radiotherapy, is the mainstay treatment for brain metastasis and anti-human epidermal growth factor receptor type 2 (HER2)-targeted therapy has been shown to be efficacious for HER2+ breast cancer (BC) patients with brain metastasis. However, Clinical studies comparing the combined effects of the two treatments are lacking. This study sought to investigate the efficacy and safety of pyrotinib and radiotherapy versus pyrotinib-based therapy in treating HER2+ BC patients with brain metastasis. Methods: This retrospective, observational study collected data from 79 HER2+ BC patients with brain metastasis who received pyrotinib-based therapy from May 2018 to December 2021. Among these patients, 35 received pyrotinib-based therapy concurrently with, or within 3 months before or after, brain radiotherapy (Group A), and 44 received pyrotinib-based therapy as the primary regimen (with no restriction as to whether they had received brain radiotherapy previously or not, the interval between receiving radiotherapy and receiving pyrotinib was >3 months) (Group B). Patient information was collected by the Electronic Medical Records System. The primary endpoints were progression-free survival (PFS) and overall survival (OS). The secondary endpoints were the objective response rate (ORR), the clinical benefit rate (CBR), and safety. The assessment of adverse effects was based on CTCAE5.0. Results: The intracranial ORRs were 48.6% in Group A and 20.5% (9/44) in Group B (P=0.015). The intracranial CBRs were 80.0% in Group A and 65.9% in Group B. The median intracranial PFS times (IC-PFS) were 15.0 months and 9.0 months in Group A and Group B, respectively (P=0.385). There was no statistically significant difference in OS between the 2 groups (95.0 vs. 98.0 months, P=0.872). The subgroup analysis showed that patients with active brain metastasis who received pyrotinib and radiotherapy had a longer IC-PFS time than those who received pyrotinib-based therapy(P=0.056). No serious adverse reactions (e.g., acute brain edema, cognitive dysfunction, or treatment-related death events) were observed. Conclusions: Pyrotinib combined with radiotherapy is recommended for HER2+ breast cancer active brain metastasis patients who can tolerate radiotherapy and pyrotinib. Pyrotinib-based therapy may be considered for patients who cannot tolerate radiotherapy and pyrotinib.

Phase II Prospective Study of Trastuzumab in Combination with S-1 and Oxaliplatin (SOX100) Therapy for HER2-Positive Advanced Gastric Cancer.

PURPOSE: The standard first-line treatment for human epidermal growth factor receptor type 2 (HER2)-positive advanced gastric cancer (AGC) is trastuzumab in combination with cisplatin and fluoropyrimidines. We evaluated the efficacy and safety of S-1 and oxaliplatin (100 mg/m2) (SOX100) combined with trastuzumab, a monoclonal antibody against HER2 for HER2-positive AGC. METHODS: In this single-arm, multicenter phase II study, patients with HER2-positive AGC received S-1 (80-120 mg per day) orally on days 1-14, oxaliplatin (100 mg/m2) intravenously on day 1, and trastuzumab (8 mg/kg on day 1 of the first cycle, followed by 6 mg/kg every 3 weeks) intravenously. The primary end point was 1-year survival rate. The secondary end points included overall survival (OS), progression-free survival (PFS), overall response rate (ORR), and safety. RESULTS: A total of 25 patients from six centers were enrolled from December 2015 to March 2020. In the 25 patients evaluable for analysis, the 1-year survival rate was 70.8% [90% confidence interval (CI) = 55.5-86.1%], whereas the median OS, PFS, and ORR were 17.8 (95% CI 10.5-22.9) months, 7.6 (95% CI 5.0-10.9) months, and 75.0% (95% CI 53.3-90.2), respectively. Major grade 3/4 adverse events included anorexia (20%), anemia (16%), peripheral sensory neuropathy (16%), and diarrhea (15%). CONCLUSION: SOX100 combined with trastuzumab was effective with a favorable safety profile in patients with HER2-positive AGC.

Refining Therapy in Patients with HER2-Positive Breast Cancer with Central Nervous System Metastasis.

Background: Brain metastasis (BM) is a major clinical problem in metastatic breast cancer (MBC), occurring in 50% of patients with human epidermal growth factor receptor 2-positive (HER2+) breast cancer. Historically omitted from clinical trials, recent studies of novel HER2-targeted agents have focused on HER2+ BM patients, addressing stable but also progressing BM and leptomeningeal carcinomatosis (LMC). Summary: This review aimed to summarize the most relevant data on treating patients with HER2+ BM and LMC. Key Messages: The treatment paradigm for patients with HER2+ MBC has changed. Local therapies play an important role, but accumulating evidence on the intracranial activity and clinical benefit of anti-HER2 targeting therapies might lead to a shift in the paradigm on treating BM in the next few years towards more widespread use of systemic therapy.

Trastuzumab With S-1 Plus Cisplatin in HER2-positive Advanced Gastric Cancer Without Measurable Lesions: OGSG 1202.

BACKGROUND/AIM: Trastuzumab with S-1 plus cisplatin was proved to be effective for human epidermal growth factor receptor type 2 (HER2)-positive advanced gastric cancer with measurable lesions. However, the efficacy and safety of this regimen in the absence of measurable lesions are unknown. PATIENTS AND METHODS: Patients with HER2-positive gastric cancer without measurable lesions received cisplatin plus trastuzumab intravenously on day 1 and oral S-1 on days 1-14 of a 21-day cycle. The primary end-point was overall survival, and 40 patients were planned to be enrolled. RESULTS: Fifteen patients were enrolled. The median overall survival was 14.4 months. The 1- and 3-year overall survival rates were 66.7 % and 26.7 %, respectively. Major grade 3-4 adverse events included neutropenia (47%), anemia (40%), diarrhea (20%), nausea (20%), and anorexia (20%). CONCLUSION: Trastuzumab with S-1 plus cisplatin might be effective and tolerable for HER2-positive advanced gastric cancer without measurable lesions.

Associations in tumor infiltrating lymphocytes between clinicopathological factors and clinical outcomes in estrogen receptor-positive/human epidermal growth factor receptor type 2 negative breast cancer.

The value of assessing tumor infiltrating lymphocytes (TILs) in estrogen receptor (ER) positive/human epidermal growth factor receptor type 2 (HER2) negative breast cancer has yet to be determined. In the present study, a total of 184 cases with early distant recurrence detected within 5 years following the primary operation, 134 with late distant recurrence diagnosed following 5 years or longer and 321 controls without recurrence for >10 years following starting the initial treatment for ER-positive/HER2 negative breast cancer, registered in 9 institutions, were analyzed. The distributions of TILs and their clinical relevance were investigated. TIL distributions did not differ significantly among the early, late and no recurrence groups, employing a 30% cut-off point as a dichotomous variable. In those who had received adjuvant chemotherapy as well as endocrine therapy, a trend toward higher TIL proportions was detected when the early recurrence group was compared with the no recurrence group employing the 30% cut-off point (P=0.064). The TIL distributions were significantly associated with nodal metastasis (P=0.004), ER status (P=0.045), progesterone receptor (PgR) status (P=0.002), tumor grade (P=0.021), and the Ki67 labeling index (LI) (P=0.002) in the no recurrence group and with the Ki67 LI in the recurrence groups (P=0.002 in early recurrence group, P=0.023 in late recurrence group). High TIL distributions also predicted shorter survival time following the detection of recurrence (P=0.026). However, these prognostic interactions were not significant in multivariate analysis (P=0.200). The present retrospective study demonstrated no significant interaction between TIL proportions and the timing of recurrence. However, higher TIL proportions were observed in breast cancer patients with aggressive biological phenotypes, which tended to be more responsive to chemotherapy. The clinical relevance of stromal TILs for identifying patients who would likely benefit from additional therapies merits further investigation in a larger patient population.

Correlation of digital mammography and digital breast tomosynthesis features of self-detected breast cancers with human epidermal growth factor receptor type 2/neu status.

CONTEXT: Breast cancer is a heterogeneous disease with several histological subtypes. Its prognosis and management are influenced by human epidermal growth factor receptor type 2 (HER2/neu) expression. Varying grades of HER2/neu overexpression are likely to have different morphological features. Digital breast tomosynthesis (DBT) enhances lesion visibility and hence that it may reveal features closer to histomorphological findings. AIMS: The aim of this study is to correlate digital mammography (DM) and DBT findings of self-detected tumors with HER2/neu status, to determine whether differences in imaging features can help predict the degrees of HER2/neu overexpression. SETTINGS AND DESIGN: Prospective study conducted in a tertiary care hospital. METHODS: For 100 consecutive patients with self-detected lumps, DM and DBT data were reviewed by two radiologists who were blinded to histopathology. Of these, 63 patients with histologically proven breast cancer were recruited and their DM and DBT findings compared and correlated with HER2neu status (scores 0-3+). STATISTICAL ANALYSIS: Pearson's Chi-squared test and Fisher's exact test were used (SPSS version 22.0, IBM). RESULTS: Morphology of lesions at both DM and DBT varied with HER2/neu status (P = 0.04 and 0.015, respectively). HER2-0 tumors mostly presented as masses without microcalcifications (88.8%), while most of HER2-3+ tumors as masses or asymmetries with microcalcifications (61.9%). The presence or absence of calcifications varied significantly with HER2/neu status. Breast imaging-reporting and data system (BI-RADS) scoring varied significantly (P < 0.001) with higher HER2 signal, more frequently associated with BI-RADS 5 score. CONCLUSION: DM and DBT features vary with the intensity of HER2 immunostaining. Higher BI-RADS scores, microcalcifications, and spiculated margins are frequently associated with HER2/neu 3+ lesions.

MAP2 IHC detection: a marker of antigenicity in CNS tissues.

Immunohistochemistry (IHC) is used to detect antibody-specific antigens in tissues; the results depend on the ability of the primary antibodies to bind to their antigens. Therefore, results depend on the quality of preservation of the specimen. Many investigators have overcome the deleterious effects of over-fixation on the binding of primary antibodies to specimen antigens using IHC, but if the specimen is under-fixed or fixation is delayed, false negative results could be obtained despite certified laboratory practices. Microtubule-associated protein 2 (MAP2) is an abundant microtubule-associate protein that participates in the outgrowth of neuronal processes and synaptic plasticity; it is localized primarily in cell bodies and dendrites of neurons. MAP2 immunolabeling has been reported to be absent in areas of the entorhinal cortex and hippocampus of Alzheimer's disease brains that were co-localized with the dense-core type of amyloid plaques. It was hypothesized that the lack of MAP2 immunolabeling in these structures was due to the degradation of the MAP2 antigen by the neuronal proteases that were released as the neurons lysed leading to the formation of these plaques. Because MAP2 is sensitive to proteolysis, we hypothesized that changes in MAP2 immunolabeling may be correlated with the degree of fixation of central nervous system (CNS) tissues. We detected normal MAP2 immunolabeling in fixed rat brain tissues, but MAP2 immunolabeling was decreased or lost in unfixed and delayed-fixed rat brain tissues. By contrast, two ubiquitous CNS-specific markers, myelin basic protein and glial fibrillary acidic protein, were unaffected by the degree of fixation in the same tissues. Our observations suggest that preservation of various CNS-specific antigens differs with the degree of fixation and that the lack of MAP2 immunolabeling in the rat brain may indicate inadequate tissue fixation. We recommend applying MAP2 IHC for all CNS tissues as a pre-screen to assess the quality of the tissue preservation and to avoid potentially false negative IHC results.

A phase II prospective study of the trastuzumab combined with 5-weekly S-1 and CDDP therapy for HER2-positive advanced gastric cancer.

BACKGROUND: We evaluated the efficacy and safety of 5-weekly S-1 and cisplatin combined with trastuzumab, a monoclonal antibody against human epidermal growth factor receptor type 2 (HER2) for HER2-positive advanced gastric cancer (AGC). METHODS: This phase II study treatment consisted of S-1 (80-120 mg per day) orally on day 1-21, cisplatin (60 mg/m(2)) intravenously on day 8, and trastuzumab (8 mg/kg on day 1 of the first cycle, followed by 6 mg/kg every 3 weeks) intravenously. The primary end point was 1-year survival rate. The secondary end points included overall survival, progression-free survival (PFS), response rate (RR), and safety. RESULTS: A total 22 patients from seven centers were enrolled. In the 20 patients evaluable for analysis, the 1-year survival rate was 70 % (95 % confidence interval (CI) 49.9-90.1 %), and median survival time, PFS, and RR were 15.3, 7.5 months and 41.2 %, respectively. Major grade 3/4 adverse events were neutropenia (30 %), anorexia (30 %), leukopenia (25 %), fatigue (20 %), and anemia (15 %). CONCLUSIONS: Five-weekly S-1 and cisplatin combined with trastuzumab showed effective with favorable safety profile in patients with HER2-positive AGC.

Cancer stem cells and HER2 positive breast cancer: The story so far.

Human Epidermal Growth Factor Receptor type 2 (HER2) gene amplification and/or protein overexpression is observed in patients suffering from HER2+ breast cancer. This subtype of breast cancer has improved prognosis due to availability of anti-HER2 therapy. However, drug resistance and tumor recurrence still remains a major concern. Cancer Stem Cells (CSCs) are believed to constitute the subset of cell population that is resistant to drug treatment and possesses characteristics of stem cells. CSCs enable the tumors to thrive despite major insults. This review provides a comprehensive idea about the concept of CSCs in context of HER2+ breast cancer by providing the description of the markers that are used for the identification of CSCs and by elucidating the signaling pathways that are associated with HER2+ breast CSCs. Furthermore, the review also describes the interaction of HER2 with those signaling pathways and the future of targeting CSCs in HER2+ breast cancer.

Current and emerging therapies in unresectable and recurrent gastric cancer.

Gastric cancer is one of the most lethal cancers worldwide despite many advances and options in therapy. As it is often diagnosed at an advanced stage, prognosis is poor with a median overall survival of less than twelve months. Chemotherapy remains the mainstay of treatment for these patients but it confers only a moderate survival advantage. There remains a need for new targeted treatment options and a way to better define patient populations who will benefit from these agents. In the past few years, there has been a better understanding of the biology, molecular profiling, and heterogeneity of gastric cancer. Our increased knowledge has led to the identification of gastric cancer subtypes and to the development of new targeted therapeutic agents. There are now two new targeted agents, trastuzumab and ramucirumab, that have recently been approved for the treatment of advanced and metastatic gastric cancer. There are also many other actively investigated targets, including epidermal growth factor receptor, the phosphatadylinositol 3-kinase/protein kinase B/mammalian target of rapamycin pathway, c-Met, poly ADP-ribose polymerase, and immune checkpoint inhibition. In this review, we discuss the current management of advanced gastric cancer as well as emerging targeted therapies and immunotherapy.

Imaging of HER2 may improve the outcome of external irradiation therapy for prostate cancer patients.

Prostate cancer (PCa) is the most common type of cancer among males. Human epidermal growth factor receptor type 2 (HER2) expression in PCa has been reported by several studies and its involvement in the progression towards androgen-independent PCa has been discussed. External irradiation is one of the existing therapies, which has been demonstrated to be efficient in combination with androgen deprivation therapy for the treatment of advanced PCa. However, 20-40% of patients develop recurrent and more aggressive PCa within 10 years. The current study investigates the involvement of HER2 in survival and radioresistance in PCa cells and we hypothesized that, by monitoring HER2 expression, treatment may be personalized. The PCa cell lines, LNCap, PC3 and DU-145, received a 6 Gy single dose of external irradiation. The number of PC3 cells was not affected by a single dose of radiation, whereas a 5-fold decrease in cell number was detected in LNCap (P<0.00001) and DU-145 (P<0.0001) cells. The HER2 expression in PC3 exhibited a significant increase post irradiation, however, the expression was stable in the remaining cell lines. The administration of trastuzumab post-irradiation resulted in a 2-fold decrease in the PC3 cell number, while the drug did not demonstrate additional effects in LNCap and DU-145 cells, when compared with that of irradiation treatment alone. The results of the present study demonstrated that an increase in membranous HER2 expression in response to external irradiation may indicate cell radioresistance. Furthermore, imaging of HER2 expression prior to and following external irradiation may present a step towards personalized therapy in PCa.