Immunohistochemical study of c-erbB-2 protein in colorectal cancer and the correlation with patient survival

HER2 targeted therapy in colorectal Cancer: Current landscape and future directions

Colorectal cancer (CRC) is one of the most common causes of tumor-related deaths globally. Despite recent improvements in the comprehensive therapy of malignancy, metastatic CRC continues to have a poor prognosis. Human epidermal growth factor receptor 2 (HER2) is an established oncogenic driver, which is successfully targeted for breast and gastric cancers. Approximately 5% of CRC patients carry somatic HER2 mutations or gene amplification. In 2019, the U.S. Food and Drug Administration have approved trastuzumab and pertuzumab in combination with chemotherapy for the treatment of HER2-positive metastatic CRC. This approval marked a significant milestone in the treatment of CRC, as HER2-positive patients now have access to targeted therapies that can improve their outcomes. Yet, assessment for HER2 overexpression/ amplification in CRC has not been standardized. The resistance mechanisms to anti-HER2 therapy have been not clearly investigated in CRC. Although many unknowns remain, an improved understanding of these anti-HER2 agents will be essential for advanced CRC. In this review, we provide an overview of the role of HER2 in CRC as an oncogenic driver, a prognostic and predictive biomarker, and a clinically actionable target, as well as the current progress and challenges in the field.

A comprehensive appraisal of HER2 heterogeneity in HER2-amplified and HER2-low colorectal cancer

BACKGROUND

This study aimed to elucidate the clinicopathological and molecular features of HER2-amplified and HER2-low colorectal cancers (CRCs). We also characterised HER2 expression statuses in CRCs focusing on their intratumoral heterogeneity and alterations in metastatic lesions to establish practical HER2 status assessment.

METHODS

We evaluated 1009 CRCs for HER2 expression and HER2 amplification by immunohistochemistry and FISH, respectively, and correlated the results to clinicopathological and molecular data. For HER2-positive tumours, HER2 expression in metastatic lesions was also assessed.

RESULTS

Twenty-five HER2-amplified (2.5%) and 46 HER2-low tumours (4.6%) were identified. HER2-amplified tumours consistently lacked a mucinous component and HER2-low tumours tended to be in the right colon, but no other clinicopathological features were noted. KRAS, NRAS or BRAF mutations were detected in only two HER2-amplified tumours (8%), whereas 23 HER2-low tumours (50%) had one of these mutations. Most HER2-amplified and HER2-low tumours showed a homogeneous or mosaic HER2 expression pattern and a clustered heterogeneous expression pattern was rather rare. HER2 expression was maintained in most metastatic lesions in both HER2-amplified (93%) and HER2-low tumours (81%).

CONCLUSIONS

These results suggest that biopsy-based assessment of primary lesions is appropriate for the identification of CRC patients eligible for systemic HER2-targeted therapy.

Molecular mechanisms targeting drug-resistance and metastasis in colorectal cancer: Updates and beyond

Colorectal cancer (CRC) is the third most diagnosed malignancy and a major leading cause of cancer-related deaths worldwide. Despite advances in therapeutic regimens, the number of patients presenting with metastatic CRC (mCRC) is increasing due to resistance to therapy, conferred by a small population of cancer cells, known as cancer stem cells. Targeted therapies have been highly successful in prolonging the overall survival of patients with mCRC. Agents are being developed to target key molecules involved in drug-resistance and metastasis of CRC, and these include vascular endothelial growth factor, epidermal growth factor receptor, human epidermal growth factor receptor-2, mitogen-activated extracellular signal-regulated kinase, in addition to immune checkpoints. Currently, there are several ongoing clinical trials of newly developed targeted agents, which have shown considerable clinical efficacy and have improved the prognosis of patients who do not benefit from conventional chemotherapy. In this review, we highlight recent developments in the use of existing and novel targeted agents against drug-resistant CRC and mCRC. Furthermore, we discuss limitations and challenges associated with targeted therapy and strategies to combat intrinsic and acquired resistance to these therapies, in addition to the importance of implementing better preclinical models and the application of personalized therapy based on predictive biomarkers for treatment selection.

HER2 overexpression/amplification status in colorectal cancer: a comparison between immunohistochemistry and fluorescence in situ hybridization using five different immunohistochemical scoring criteria

OBJECTIVE

Although HER2 has gradually become an important therapeutic target for colorectal cancer (CRC), a unified and standard HER2 scoring system was still not established in CRC, and the debatable results of immunohistochemistry and fluorescence in situ hybridization (FISH) in CRC requires further exploration.

METHODS

In this study, we use five immunohistochemical (IHC) scoring criteria (i.e., IRS-p, IRS-m, GEA-s, GEA-b and HERACLES) and two FISH criteria to evaluate HER2 status, and further evaluate the correlation between HER2 status and clinicopathological features, survival in a large, unselected Chinese cohort of 664 CRCs.

RESULTS

Finally, we set HER2/CEP17 ratio ≥ 2.0, or an average HER2 copy number ≥ 6.0 as FISH-positive threshold and the amplification rate of HER2 gene was 7.08% (47/664).The HER2 positivity (IHC 3+) was 2.71%, 3.16%, 2.56%, 2.71% and 3.16%, according to the IHC scoring criteria of IRS-p, IRS-m, GEA-s, GEA-b and HERACLES, respectively. Set FISH results as the golden standard; receiver-operating characteristic analysis showed that IRS-p had both high sensitivity and specificity than other IHC scoring systems to evaluate HER2 status. Based on IRS-p criterion, There were significant differences in tumor differentiation (p = 0.038), lymphatic vascular invasion (p = 0.001), pN stage (p value = 0.043), and overall survival (p < 0.001) among IHC score 0-3 + groups. Meanwhile, there were significant differences in pT stage (p = 0.031), pN stage (p = 0.009) and overall survival (p < 0.001) among FISH subgroups.

CONCLUSION

The IRS-p criterion was more suitable for assessing the HER2 status in CRC patients than other IHC criteria. Whereas for FISH scoring system, only HER2/CEP17 < 2.0, meanwhile HER2cn < 4.0 and HER2cn ≥ 6.0 were subgroups with unique clinicopathological characteristics.

Long-term follow-up of HER2 overexpression in patients with rectal cancer after preoperative radiotherapy: A prospective cohort study

BACKGROUND

The role of HER2 overexpression in rectal cancer is controversial.

AIM

To assess the role of HER2 overexpression in the long-term prognosis of rectal cancer.

METHODS

Data from patients with locally advanced rectal cancer who underwent total mesorectal excision after short-course radiotherapy at Beijing Cancer Hospital between May 2002 and October 2005 were collected. A total of 151 tissue samples of rectal cancer were obtained using rigid proctoscopy before neoadjuvant radiotherapy, followed by immunohistochemistry and fluorescence in situ hybridisation to determine the patients’ HER2 expression status. Univariate and multivariate analyses of the associations between the clinicopathological factors and HER2 status were performed. Survival was estimated and compared using the Kaplan-Meier method based on HER2 expression status, and the differences between groups were verified using the log-rank test.

RESULTS

A total of 151 patients were enrolled in this study. A total of 27 (17.9%) patients were ultimately confirmed to be HER2-positive. The follow-up duration ranged from 9 mo to 210 mo, with a median of 134 mo. Distant metastasis and local recurrence occurred in 60 (39.7%) and 24 (15.9%) patients, respectively. HER2 positivity was significantly associated with the pre-treatment lymph node stage (pre-N) (P = 0.040), while there were no differences between HER2 status and age, sex, preoperative CEA levels (pre-CEA), T stage, and lympho-vascular invasion. In terms of prognosis, HER2 overexpression was correlated with distant metastasis (P = 0.002) rather than local recurrence (P > 0.05). The multivariate analysis demonstrated that elevated pre-CEA [P = 0.002, odds ratio (OR) = 3.277, 97.5% confidence interval (CI): 1.543-7.163], post N(+) (P = 0.022, OR = 2.437, 97.5%CI: 1.143-5.308) and HER2(+) (P = 0.003, OR = 4.222, 97.5%CI: 1.667-11.409) were risk factors for distant metastasis. The survival analysis showed that there were significant differences between rectal cancer patients in terms of disease-free survival (DFS) [hazard ratio: 1.69 (95%CI: 0.91-3.14); P = 0.048] and overall survival (OS) [1.95 (1.05-3.63); P = 0.0077].

CONCLUSION

HER2 overexpression is a potential biomarker for predicting lymph node metastasis and distant metastasis, which are associated with worse long-term DFS and OS in rectal cancer patients with locally advanced disease.

Precision Medicine in Metastatic Colorectal Cancer: Targeting ERBB2 (HER-2) Oncogene

Simple Summary

Colorectal cancer (CRC) is the third most common cancer in terms of incidence rate in adults and the second most common cause of cancer-related death in Europe. The treatment of metastatic CRC (mCRC) is based on the use of chemotherapy, anti-vascular endothelial growth factor (VEGF), and anti-epidermal growth factor receptor (EGFR) for RAS wild-type tumors. Precision medicine tries to identify molecular alterations that could be treated with targeted therapies. Although ERBB2 (also known as HER-2) has an important therapeutic role in breast and esophagogastric cancer, there are no approved ERBB2-targeted therapies for mCRC. The purpose of this review is to describe the landscape of ERBB2-positive mCRC.

Abstract

Colorectal cancer (CRC) is the third most common cancer in terms of incidence rate in adults and the second most common cause of cancer-related death in Europe. The treatment of metastatic CRC (mCRC) is based on the use of chemotherapy, anti-vascular endothelial growth factor (VEGF), and anti-epidermal growth factor receptor (EGFR) for RAS wild-type tumors. Precision medicine tries to identify molecular alterations that could be treated with targeted therapies. ERBB2 amplification (also known as HER-2) has been identified in 2–3% of patients with mCRC, but there are currently no approved ERBB2-targeted therapies for mCRC. The purpose of this review is to describe the molecular structure of ERBB2, clinical features of these patients, diagnosis of ERBB2 alterations, and the most relevant clinical trials with ERBB2-targeted therapies in mCRC.

Mind the target: human epidermal growth factor receptor 2 in colorectal cancer

PURPOSE OF REVIEW

In this article, we briefly summarise the current knowledge about human epidermal growth factor receptor 2 (HER2) alterations in colorectal cancer (CRC) and provide an overview of the latest published evidence especially regarding standardisation of detection methods/diagnostic criteria, prognostication, prediction and targeted treatments.

RECENT FINDINGS

Over the last 18 months, the results of many studies have been presented confirming the therapeutic potential of established anti-HER2 agents either as a monotherapy or in combination, as well as new anti-HER2 agents like antibody-drug-conjugates and tyrosine kinase inhibitors. Also, we have seen confirmation of the utility of liquid biopsy and ctDNA analyses as tool for HER2 detection and patient selection.

SUMMARY

Despite concerning only 5% of metastatic CRC, HER2 represents a valuable target for emerging anti-HER2 therapies that might significantly improve the outcome of these patients. Standardising HER2 detection methods/diagnostic criteria, and producing high-quality, randomised evidence are the next challenges to meet the standards of regulatory authorities and ultimately have anti-HER2 agents available for use in routine practice.

HER2 positivity as a biomarker for poor prognosis and unresponsiveness to anti-EGFR therapy in colorectal cancer

PURPOSE

To investigate the role of HER2 positivity in prognosis and unresponsiveness to anti-EGFR therapy for colorectal cancer.

METHODS

Patients who underwent primary CRC tumor resection were included. HER2 status of CRC was confirmed by immunohistochemistry and fluorescence in situ hybridization tests. Comparison of survival analysis between HER2 positivity and negativity was evaluated by a stratified log-rank test and summarized with the use of Kaplan-Meier and Cox proportional hazards methods. The treatment effects of cetuximab were further compared in full subgroup analyses.

RESULT

1240 patients were enrolled, including 763 with stage I-III CRC and 477 with stage IV CRC. 57 (4.6%) CRC patients presented HER2 positivity in the entire cohort. The survival analysis showed that patients with HER2 positivity had significantly worse disease-free survival and overall survival in stage III and IV CRC. The multivariable analysis also confirmed that HER2 positivity was a significantly independent risk factor in stage III and IV CRC. Univariate and multivariable survival analysis showed no prognostic significance of HER2 positivity in stage I-II CRC patients. Prespecified subgroup analysis showed no favorable trends in progression-free survival and overall survival for cetuximab in the patients with HER2 positivity, KRAS/NRAS/BRAF wild-type metastatic CRC (interaction P values = 0.005 and 0.014).

CONCLUSION

For stage III and IV CRC patients, HER2 positivity was confirmed as an independent prognostic risk factor. It could help predict the unresponsiveness to anti-EGFR therapy for metastatic CRC.

Novel Molecular classification of colorectal cancer and correlation with survival

Introduction

Colorectal cancer (CRC) is one of the most common cancers worldwide. This study was designed to evaluate biological patterns, explore molecular classification and correlate with survival outcome in treatment naïve CRC patients.

Methods

Over 11 years consecutive series of 435 CRC patients were operated on as primary surgical therapy. A total of 201 CRC patients were included, whose complete set of clinical information was available, and their good quality tumour blocks were retrieved. Immunohistochemistry was used for tumour analysis, and partitional clustering was performed using R software for cluster analysis.

Results

The median age was 43 (range 10–85) years; adenocarcinoma was the most commonly seen histological type. The great majority had positive CK20, CEA, E-Cadherin, Ki67, CDX2, and p53 expression. There were four distinct molecular classes found, whereas Ki67, CDX2, and p53 play the main role in partitioning. Younger age negatively impacted survival; overall and disease-specific survival was 26 months only with 50 months’ longest survival.

Conclusion

Colorectal cancer is a biologically heterogeneous disease with at least four distinct molecular patterns, where cell proliferation and gene repair mechanisms appear to play the key role.

Clinicopathological and prognostic significance of HER2 status in surgically resected colorectal liver metastases

BACKGROUND

The clinicopathological and prognostic significance of human epidermal growth factor receptor 2 (HER2) status in surgically resected colorectal liver metastases (CRLM) remains uncertain.

METHODS

HER2 expression was evaluated by immunohistochemical (IHC) in two CRLM tissue microarrays (TMAs). For samples with an IHC score of 2+ or 3+, fluorescence in situ hybridization (FISH) was performed to assess HER2 amplification. The association of HER2 amplification with clinicopathological parameters and prognosis was assessed using Fisher's exact test and Kaplan-Meier method, respectively.

RESULTS

HER2 expression was consistent between primary tumor and liver metastases in 66.9% (85/127) cases (r = 0.643, p = 0.001). After FISH validation, HER2 amplification was identified in 6.25% (13/208) patients. HER2 amplification was significantly associated with age (p = 0.017), bilobar involvement (p = 0.005) and left-sided RAS/RAF wild-type status (p = 0.002). In the overall cohort, HER2 amplification was correlated with significantly worse relapse-free survival (RFS). Further stratification revealed that among left-sided RAS/RAF wild-type cases, HER2 amplification was significantly associated with worse overall survival (OS) (30.2 vs. 50.9 months, p = 0.040) and RFS (5.77 vs. 19.97 months, p = 0.017).

CONCLUSION

HER2 amplification is more enriched in CRLMs with younger age, left-sided RAS/RAF wild-type, and bilobar involvement. Moreover, HER2 amplification predicts a poorer prognosis especially in left-sided RAS/RAF wild-type CRLMs.

Expression of Septin 2 and Her2/neu in Colorectal Cancer

Background

Colorectal cancer (CRC) is a common and lethal disease. Septin 2 belongs to the same class of GTPases as the RAS oncogenes influence the invasion and metastasis of many types of tumor cells. Furthermore, HER2/neu is involved in the tumor genesis and progression of various types of tumors. The role of both molecules is still questionable in CRC.

Aim

The aim of the study is to examine the expression of septin 2 and Her2/neu in patients with CRC.

Materials and Methods

The study was conducted on 2 groups; the first group consisted of 70 paraffin blocks for CRC patients and the second group was formed of 24 blocks from patients diagnosed as colorectal adenoma. For each adenoma and carcinoma case, a section was immunohistochemically stained using antihuman SEPT2 polyclonal antibody. For each carcinoma case, another section was immunostained using monoclonal anti-HER2/neu. The results were statistically analyzed and compared with the collected clinicopathologic data of the cases.

Results

For the carcinoma patients, there was a significant association between SEPT2 staining intensity and histologic type (P = 0.001) and grade (P < 0.001), tumor T (P = 0.001) and N (P = 0.011) stages and the presence of lymphovascular invasion (P < 0.001) and a significant association between Her2/neu immunoreactivity scores (IRSs) and histologic grade (P = 0.048), tumor T (P < 0.001) and N (P = 0.019) stages and the presence of perineural (P = 0.004) and lymphovascular (P = 0.003) invasion. In colonic adenoma patients, there was a significant relation between septin 2 IRSs and the grade of dysplasia in the adenoma (P < 0.001) and significant relation with its expression in carcinoma group (P < 0.001).

Conclusion

A potential prognostic role of septin 2 and Her2/neu for patients with CRC is suggested as expression of both markers was associated with many important prognostic clinicopathologic variables in patients of CRC.

Beyond RAS and BRAF: HER2, a New Actionable Oncotarget in Advanced Colorectal Cancer

The human epidermal growth factor receptor 2 (HER2) is a well-established oncogenic driver and a successful therapeutic target in several malignancies, such as breast and gastric cancers. HER2 alterations, including amplification and somatic mutations, have also been detected in a small but not negligible subset of patients affected by advanced colorectal cancer (aCRC). However, to date, there are no available oncotargets in this malignancy beyond RAS and BRAF that are available. Here we present an overview on the present predictive and prognostic role of HER2 expression in aCRC, as well as on its consequent potential therapeutic implications from preclinical investigations towards ongoing trials testing anti-HER2 agents in aCRC. While HER2's role as a molecular predictive biomarker for anti-EGFR therapies in CRC is recognized, HER2 prognostic value remains controversial. Moreover, thanks to the impressive and growing body of clinical evidence, HER2 is strongly emerging as a new potential actionable oncotarget in aCRC. In conclusion, in the foreseeable future, HER2-targeted therapeutic strategies may integrate the algorithm of aCRC treatment towards an increasingly tailored therapeutic approach to this disease.

Prognostic Value and Molecular Landscape of HER2 Low-Expressing Metastatic Colorectal Cancer

BACKGROUND

The prognostic value and molecular landscape of human epidermal growth factor receptor 2 (HER2) low-expressing (HER2-L) metastatic colorectal cancer (mCRC) remain unclear.

PATIENTS AND METHODS

This study enrolled patients with mCRC who had undergone surgical resection of primary tumor. Using the specimen, we evaluated HER2 expression by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). HER2 positivity was defined as follows: HER2 positivity (HER2-Pos) as IHC 3 + or IHC 2+/FISH positive, HER2-L as IHC 2+/FISH negative or IHC 1+, and HER2 negativity (HER2-Neg) as IHC 0+. Gene alterations were determined by next-generation sequencing.

RESULTS

Between 2005 and 2015, a total of 370 patients were analyzed, comprising 15 patients (4%) with HER2-Pos, 21 (6%) with HER2-L, and 334 (90%) with HER2-Neg disease. The clinicopathologic characteristics among groups had no differences. HER2-L had a significantly higher proportion of coaltered RAS mutation than HER2-Pos (P = .037). With a median follow-up of 101.8 months, HER2-L had a significantly better median overall survival than HER2-Pos (P = .029) (18.2 months in HER2-Pos vs. 33.3 in HER2-L vs. 27.9 in HER2-Neg). In 58 patients harboring wild-type RAS and receiving anti-EGFR antibody therapy, HER2-L had a better median progression-free survival tendency than HER2-Pos, with 2.2 months in HER2-Pos, 7.8 in HER2-L, and 5.1 in HER2-Neg (P = .036).

CONCLUSION

HER2-L mCRC showed a better prognosis than HER2-Pos mCRC, and it is similar to HER2-Neg mCRC. Hence, HER2-L mCRC might have different biologic behavior in terms of prognostic value and molecular landscape of mCRC, suggesting the possibility of implementation of HER2-guided clinical development against HER2-expressing mCRC.

Differential Expression of HER2 and SKP2 in Benign and Malignant Colorectal Lesions

Background:

Colorectal cancer (CRC) is the fourth most common cancer worldwide. Both HER2 and SKP2 have a carcinogenic role in CRC making them attractive targets for tailored treatment. This work aims to correlate HER2 and SKP2 protein expression as well as HER2 gene amplification with clinicopathological parameters aiming at identifying potential candidates for targeted therapy.

Methods:

This Study was conducted on 127 paraffin-embedded tissue samples of different colorectal lesions [controls, chronic colitis, ulcerative colitis (UC), hyperplastic polyps (HPs), adenomas and CRCs] to investigate HER2 and SKP2 expression by immunohistochemistry (IHC), Selected CRC cases [equivocal (2+) and positive (3+) by IHC] were further evaluated by ISH (CISH and SISH ) to assess HER2 gene amplification.

Results:

Chronic colitis, UC, HPs and adenomas were HER2-negative. HER2 positivity (scores 2+ and 3+) was found only in15% of CRCs. Both SISH and CISH showed the same results with high concordance as 66.7% of equivocal and 100% of positive cases showed amplification of HER2 gene. SKP2 positivity was detected in 26.7% and 45% of adenomas and CRCs respectively, while other studied groups were negative. A significant correlation was noted between HER2 and SKP2 expression.

Conclusion:

A small percent of CRCs exhibited HER2 gene amplification, which would be potential candidates for anti HER2 therapy whereas IHC could be a primary screening test for patient selection. A potential carcinogenic role of SKP2 was suggested by the findings that SKP2 expression was undetectable in normal colonic mucosa but significantly increases from adenoma to carcinoma, hoping adenoma patients to get benefit from targeted therapy.

HER2 in Colorectal Carcinoma: Are We There yet?

HER2 (ERBB2) is a member of the ERBB family of receptor tyrosine kinases and functions to drive signaling in the RAS/RAF/MEK/ERK and PI3K/AKT/mTOR pathways. Overall, approximately 2-3% of CRCs exhibit ERBB2 amplification. Multiple phase II clinical trials have now shown that ERBB2 amplification can be predictive of response to anti-ERBB2 targeted therapy. Consequently, recently released guidelines from the National Comprehensive Cancer Network recommend treatment with anti-ERBB2 targeted therapy for RAS wild-type, ERBB2-amplified metastatic CRC. While circumspection is still needed, ERBB2 amplification has now emerged as the next standard-of-care biomarker for metastatic CRC, expanding targeted therapy options for these patients.

Prevalence, prognosis and predictive status of HER2 amplification in anti-EGFR-resistant metastatic colorectal cancer

Numerous inherent and acquired genetic alterations have been demonstrated with resistance to anti-epidermal growth factor receptor (anti-EGFR) therapy in metastatic colorectal cancer (mCRC) patients. Although the common oncogenic driver mutations identified include KRAS, NRAS, BRAF, and PI3K, recent studies report a vital role played by human epithelial growth factor receptor-2 (HER2) amplification in acquired resistance to anti-EGFR therapy. HER2 amplification has been associated with poor prognosis in many malignancies including breast and gastric cancer and is also a negative predictor of anti-EGFR therapy. Given the relevance of HER2 amplification in conferring an anti-EGFR resistance, this paper reviews the prevalence of HER2 amplification in mCRC while exploring the prognostic and predictive values of this biomarker. Further, we also discuss the results of the studies that explored the utilization of anti-HER2-targeted therapies in mCRC. HER2-directed therapies have the ability to change the treatment algorithm in clinically relevant small subset of patients with HER2-amplified mCRC.

KRAS, NRAS, BRAF, HER2 and microsatellite instability in metastatic colorectal cancer - practical implications for the clinician

Background Colorectal cancer is a successful model of genetic biomarker development in oncology. Currently, several predictive or prognostic genetic alterations have been identified and are used in clinical practice. The RAS gene family, which includes KRAS and NRAS act as predictors for anti-epithelial growth factor receptor treatment (anti-EGFR), and it has been suggested that NRAS mutations also play a role in prognosis: patients harboring NRAS alterations have a significantly shorter survival compared to those with wild type tumours. BRAF V600E mutations are rare and occur mostly in tumors located in the ascending colon in elderly female patients. BRAF is instrumental in establishing prognosis: survival is shorter by 10-16 months in BRAF-mutant patients, and BRAF may be a negative prognostic factor for patients who undergo hepatic or pulmonary metastasectomy. Moreover, this mutation is used as a negative predictive factor for anti-EGFR therapies. Two new biomarkers have recently been added to the metastatic colorectal cancer panel: HER2 and microsatellite instability. While HER2 is still being investigated in different prospective studies in order to validate its prognostic role, microsatellite instability already guides clinical decisions in substituted with advanced colorectal cancer. Conclusions There are current evidences that support using above mentioned genetic biomarkers to better identify the right medicine that is supposed to be used in the right patient. This approach contributes to a more individualized patient-oriented treatment in daily clinical practice.

Clinical significance of HER2 and EGFR expression in colorectal cancer patients with ovarian metastasis

Background

EGFR and HER2 overexpression has been reported to play important roles in colorectal cancer (CRC) development and metastasis. Ovarian metastasis is rare yet is one of the most malignant metastases of CRC, but very few studies have focused on its biological features. This study aimed to investigate the expression of EGFR and HER2 in ovarian metastases of CRC and to reveal their clinical significance.

Methods

The expression of HER2 and EGFR in both primary tumours and ovarian metastases was analysed by immunohistochemistry (IHC) in 31 CRC patients with ovarian metastases as well as in the primary tumours of 26 CRC patients with non-ovarian metastases. The overall survival time was calculated with a Kaplan-Meier survival curve and compared with a log-rank test.

Results

HER2 positivity in primary tumours was significantly higher in patients with ovarian metastases than in those with non-ovarian metastases (54.5% vs. 36.4%, P < 0.05). The EGFR-positive rate in primary lesions was not significantly different between patients with ovarian metastases and those with non-ovarian metastases (63.6% vs. 58.3%, P > 0.05). HER2 expression was not correlated with age, primary tumour site, tumour differentiation, tumour diameter or vascular cancer embolus (P > 0.05). The positive rates of HER2 and EGFR in ovarian metastases were 44.8 and 69.0%, respectively. HER2 expression in ovarian metastases was correlated with peritoneal metastasis and bilateral ovarian metastasis (P < 0.05) but not with age, synchronous or metachronous ovarian metastases and the primary tumour site (P > 0.05). There was no significant correlation between EGFR expression and the clinicopathological features in ovarian metastases (P > 0.05). CRC patients with HER2-positive ovarian metastases showed a shortened overall survival time compared to that of CRC patients with HER2-negative metastases (17.0 ± 5.2 vs. 32.0 ± 8.3 months).

Conclusion

Our studies revealed that EGFR and HER2 are highly expressed in the primary tumours and metastases of CRC patients with ovarian metastases. HER2 positivity may be a negative prognostic predictor in patients with ovarian metastases.

HER2-targeted therapy: an emerging strategy in advanced colorectal cancer

INTRODUCTION

Colorectal cancer (CRC) is one of the most common malignant tumors; it is a focus of research globally, but the identification of clinically actionable oncogenic drivers remains elusive. Human epidermal growth factor receptor 2 (HER2) activation is present in approximately 5% of CRC and has acquired resistance to epidermal growth factor receptor (EGFR)-targeted therapy. Early clinical trials suggest an emerging role for personalized HER2-targeted therapy in a subset of metastatic CRC.

AREAS COVERED

This manuscript reviews the relevance of HER2 activation in CRC and its potential role as a target for therapy. A literature search was conducted in June 2018 of MEDLINE and EMBASE databases for published preclinical and clinical studies; abstracts of international cancer meetings (AACR, ASCO, and ESMO) were also reviewed.

EXPERT OPINION

HER2 is activated in a small but relevant proportion of CRC patients (particularly left-side, RAS wild-type, anti-EGFR resistant tumors). Dual HER2 blockade with monoclonal antibodies (mAbs) (trastuzumab and pertuzumab) or the combination of mAbs with tyrosine kinase inhibitors (trastuzumab and lapatinib) induces durable tumor responses in about one-third of HER2-positive CRC refractory to standard systemic therapy. Although immature, these results are remarkable and anticipate an expanding role for HER2 as a therapeutic target in CRC.

Noninvasive Biomarkers of Colorectal Cancer: Role in Diagnosis and Personalised Treatment Perspectives

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths worldwide. It has been estimated that more than one-third of patients are diagnosed when CRC has already spread to the lymph nodes. One out of five patients is diagnosed with metastatic CRC. The stage of diagnosis influences treatment outcome and survival. Notwithstanding the recent advances in multidisciplinary management and treatment of CRC, patients are still reluctant to undergo screening tests because of the associated invasiveness and discomfort (e.g., colonoscopy with biopsies). Moreover, the serological markers currently used for diagnosis are not reliable and, even if they were useful to detect disease recurrence after treatment, they are not always detected in patients with CRC (e.g., CEA). Recently, translational research in CRC has produced a wide spectrum of potential biomarkers that could be useful for diagnosis, treatment, and follow-up of these patients. The aim of this review is to provide an overview of the newer noninvasive or minimally invasive biomarkers of CRC. Here, we discuss imaging and biomolecular diagnostics ranging from their potential usefulness to obtain early and less-invasive diagnosis to their potential implementation in the development of a bespoke treatment of CRC.

Molecular targets of Chinese herbs: a clinical study of metastatic colorectal cancer based on network pharmacology

Increasing evidence has shown that Chinese herbal medicine (CHM) has promising therapeutic effects in colorectal cancer (CRC); however, the active ingredients and potential targets remain unclear. In this study, we aimed to investigate the relative molecular targets of the Chinese herbs that have been found effective in treating metastatic CRC (mCRC) based on clinical data and network pharmacology. In multivariate analysis CHM resulted an independent prognostic factor. The hazard ratio was 0.103 (95% confidence interval = 0.064-0.164; P < 0.001). Compared with the non-CHM group, the median survival time of the CHM group was also improved (40 versus 12 months; P < 0.001). Eighteen out of 295 herbs showed significant correlation with survival results (P < 0.05). Bioinformatics analysis indicated that the 18 herbs realize anti-CRC activity mainly through suppressing the proliferative activity of ERBB2, peroxisome proliferator-activated receptor gamma, and retinoid X receptor, suppressing angiogenesis via inhibition of VEGFR and VEGFA expression, inhibiting the phosphatidylinositol-3-kinase/AKT1 signaling pathway directly through SRC and AKT1, and reducing tumor necrosis factor-induced inflammation.

Targeting the human epidermal growth factor receptor 2 (HER2) oncogene in colorectal cancer

Human epidermal growth factor receptor 2 (HER2) is an oncogenic driver, and a well-established therapeutic target in breast and gastric cancers. Using functional and genomic analyses of patient-derived xenografts, we previously showed that a subset (approximately 5%) of metastatic colorectal cancer (CRC) tumors is driven by amplification or mutation of HER2. This paper reviews the role of HER2 amplification as an oncogenic driver, a prognostic and predictive biomarker, and a clinically actionable target in CRC, considering the specifics of HER2 testing in this tumor type. While the role of HER2 as a biomarker for prognosis in CRC remains uncertain, its relevance as a therapeutic target has been established. Indeed, independent studies documented substantial clinical benefit in patients treated with biomarker-driven HER2-targeted therapies, with an impact on response rates and duration of response that compared favorably with immunotherapy and other examples of precision oncology. HER2-targeted therapeutic strategies have the potential to change the treatment paradigm for a clinically relevant subgroup of metastatic CRC patients.

Membranous or Cytoplasmic HER2 Expression in Colorectal Carcinoma: Evaluation of Prognostic Value Using Both IHC & BDISH

BACKGROUND

Human epidermal growth factor recptor-2 (HER2) was identified as a driver gene in several types of cancers with both prognostic and predictive value. However, the molecular association of HER2 gene mutation with HER2 gene amplification and/or protein expression in cancer tissues has not been clearly defined. Moreover, there is little information available on HER2 status role in tumor progression and metastasis in colorectal carcinoma (CRC) compared to other solid tumors. The aim of this study was to evaluate both HER2 amplification and protein expression profiles using immunohistochemistry (IHC) and bright-field dual in situ hybridization (BDISH) techniques, respectively.

PATIENTS AND METHODS

Tissue microarray (TMA) was constructed to accommodate a total of 243 CRC formalin-fixed paraffin embedded (FFPE) samples of consent patients and stained by IHC and BDISH methods. The expression patterns of HER2 protein status were evaluated and correlated to HER2 gene amplification status and then assessed for its prognostic value.

RESULTS

The expression profile of 58% samples showed cytoplasmic expression patterns of different categories. Interestingly, only 1% showed strong (+3) membranous expression pattern of HER2 with perfect match with their corresponding gene amplification status (>2). However, the cytoplasmic HER2 protein status did not show significant correlation with most clinicopathological features and survival outcomes except with age (p = 0.04) and tumor size (p = 0.03).

CONCLUSION

We demonstrated that the membranous HER2 gene/protein status is infrequent, while the main fraction of HER2 overexpression was cytoplasmic and lacking prognostic value. This cytoplasmic HER2 overexpression was induced through a gene-amplification independent pathway, making the HER2 gene status evaluation approach in those cases not worthy. Further investigations about the molecular pathways of the cytoplasmic HER2 protein in CRC and its associations with survival outcomes are required to allow either a breakthrough in CRC management; or to confirm the hypothesis of a marginal role in CRC onset and progression.

Association of human epidermal growth factor receptor-2 expression and clinicopathological findings in patients with colorectal cancer

BACKGROUND

To determine the frequency of HER-2 overexpression in colorectal cancer (CRC) patients, and to explore the relationship between clinicopathological prognostic factors and their effects on survival, based on immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) analysis.

MATERIALS AND METHODS

The study included 80 patients with a histologically proven diagnosis of CRC that received adjuvant FOLFOX-4 chemotherapy at our department between March 2006 and September 2010. Patient data were analyzed retrospectively.

RESULTS

The median follow-up period and age of the patients were 24 months and 59 years, respectively. In immunohistochemical staining, 3+ staining was found in 2 patients (2.5%) while 2+ was in 13 (16%) . FISH for HER-2 was performed for all of these 15 patients; samples which were 3+ showed positivity but the ones with 2+ were negative. There was no significant correlation between HER-2 expression and age, gender, tumor localization, histological subtype, grade, lymphovascular and perineural invasion, or pTN stage (P>0.05), even when the patients with HER-2 overexpression were analyzed separately. There was also no significant relationship between progression-free survival (PFS) and overall survival (OS), and HER-2 expression, gender, tumor localization, obstruction-perforation, bleeding, histological type, grade, lymphovascular and perineural invasion, or pT staging (P>0.05); however, there was a significant relationship between lymph node involvement, and PFS and OS (P<0.05).

CONCLUSIONS

Evaluation of HER-2 overexpression in a more comprehensive, multi-center, prospective trial with standardized methods will be an appropriate approach.

HER2 overexpression and amplification as a potential therapeutic target in colorectal cancer: analysis of 3256 patients enrolled in the QUASAR, FOCUS and PICCOLO colorectal cancer trials

HER2 overexpression/amplification is linked to trastuzumab response in breast/gastric cancers. One suggested anti‐EGFR resistance mechanism in colorectal cancer (CRC) is aberrant MEK–AKT pathway activation through HER2 up‐regulation. We assessed HER2‐amplification/overexpression in stage II–III and IV CRC patients, assessing relationships to KRAS/BRAF and outcome. Pathological material was obtained from 1914 patients in the QUASAR stage II–III trial and 1342 patients in stage IV trials (FOCUS and PICCOLO). Tissue microarrays were created for HER2 immunohistochemistry. HER2‐amplification was assessed using FISH and copy number variation. KRAS/BRAF mutation status was assessed by pyrosequencing. Progression‐free survival (PFS) and overall survival (OS) data were obtained for FOCUS/PICCOLO and recurrence and mortality for QUASAR; 29/1342 (2.2%) stage IV and 25/1914 (1.3%) stage II–III tumours showed HER2 protein overexpression. Of the HER2‐overexpressing cases, 27/28 (96.4%) stage IV tumours and 20/24 (83.3%) stage II–III tumours demonstrated HER2 amplification by FISH; 41/47 (87.2%) also showed copy number gains. HER2‐overexpression was associated with KRAS/BRAF wild‐type (WT) status at all stages: in 5.2% WT versus 1.0% mutated tumours (p < 0.0001) in stage IV and 2.1% versus 0.2% in stage II–III tumours (p = 0.01), respectively. HER2 was not associated with OS or PFS. At stage II–III, there was no significant correlation between HER2 overexpression and 5FU/FA response. A higher proportion of HER2‐overexpressing cases experienced recurrence, but the difference was not significant. HER2‐amplification/overexpression is identifiable by immunohistochemistry, occurring infrequently in stage II–III CRC, rising in stage IV and further in KRAS/BRAFWT tumours. The value of HER2‐targeted therapy in patients with HER2‐amplified CRC must be tested in a clinical trial. © 2015 The Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Colorectal clinical trials: what is on the horizon?

Substantial progress has been made in the treatment of colorectal cancer, where more effective therapies have led to improved outcomes in patients with advanced disease. However, the 5-year overall survival rate remains poor. Genomic sequencing has allowed us to understand that colorectal cancer is a heterogeneous disease, where tumor-specific variants affect the prognosis and outcomes in patients. This has shaped the future directions of treatment and the development of clinical trials, including the incorporation of novel targeted therapies and investigations into the role of immunotherapy in colorectal cancer.

Expression of Human Epidermal Growth Factor Receptor-2 in Resected Rectal Cancer

The addition of trastuzumab to chemotherapy was demonstrated to be beneficial for advanced human epidermal growth factor receptor-2 (HER-2) positive gastric cancer. However, the HER-2 status of rectal cancer remains uncertain. This study aimed to determine the HER-2 expression in a large multicenter cohort of rectal cancer patients. The clinical and pathological features of 717 patients were retrospectively reviewed. All the patients were diagnosed with primary rectal adenocarcinoma without distant metastasis and took surgery directly without any preoperative anticancer treatment. HER-2 status was assessed on resected samples. A total of 99 cases with IHC3+ and 16 cases with IHC 2+ plus gene amplification were determined as HER-2 positive. 22.6% of HER-2 positive patients had local recurrence, whereas 16.9% of HER-2 negative patients did (P = 0.146). HER-2 positive tumors were more likely to have distant metastasis (P = 0.007). Univariate analysis revealed that pathological tumor stage, pathological node stage, positive margin, and lymphovascular invasion were significantly correlated with 5-year disease-free survival (DFS) and 5-year overall survival (OS). The patients with >10 dissected lymph nodes showed significantly longer OS (P = 0.045) but not DFS (P = 0.054). HER-2 negative patients had significantly better 5-year DFS (P < 0.001) and 5-year OS (P = 0.013) than those of the HER-2 positive patients. In the subgroup analysis for the early rectal cancer and locally advanced rectal cancer, HER-2 was also a poor predictor for survival. Multivariate analysis revealed that HER-2 was an independent prognostic factor for 5-year DFS (hazard ratio [HR] = 1.919, 95% confidence interval [CI] 1.415-2.605, P < 0.001) and for 5-year OS (HR = 1.549, 95% CI 1.097-2.186, P = 0.013). When the treatment was included in the analysis for locally advanced patients, HER-2 was a prognostic factor for 5-year DFS (P = 0.001) but not for 5-year OS (P = 0.106). This study confirmed that HER-2 was expressed in a part of patients with rectal cancers and might be used as a negative predictor. The results may support the trials to assess the efficacy of trastuzumab in treating HER-2 positive rectal cancer patients.

Up-regulation of HER2 by gemcitabine enhances the antitumor effect of combined gemcitabine and trastuzumab emtansine treatment on pancreatic ductal adenocarcinoma cells

Background

Although pancreatic ductal adenocarcinomas (PDAs) widely express HER2, the expression level is generally low. If HER2 expression in PDA cells could be enhanced by treatment with a given agent, then combination therapy with that agent and trastuzumab emtansine (T-DM1), a chemotherapeutic agent that is a conjugate of trastuzumab, might lead to significant antitumor effects against PDA.

Methods

Cell proliferation was examined by spectrophotometry. HER2 expression was examined by flow cytometry, immunoblot and quantitative reverse transcription polymerase chain reaction. T-DM1 binding to cells was examined by flow cytometry and enzyme-linked immunosorbent assay.

Results

Out of 5 tested human PDA cell lines, including MIA PaCa-2, three showed increases in HER2 expression after gemcitabine (GEM) treatment. The binding of T-DM1 to GEM-treated MIA PaCa-2 cells was higher than to untreated MIA PaCa-2 cells. Treatment with GEM and T-DM1 showed synergic cytotoxic effects on MIA PaCa-2 cells in vitro. Cells in the G2M phase of the cell cycle were retained after GEM treatment and showed higher levels of HER2 expression, possibly contributing to the synergic effect of GEM and T-DM1.

Conclusions

Combined treatment with GEM and T-DM1 might confer a potent therapeutic modality against PDA as a result of GEM-mediated HER2 up-regulation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1772-1) contains supplementary material, which is available to authorized users.

Does overexpression of HER-2 correlate with clinicopathological characteristics and prognosis in colorectal cancer? Evidence from a meta-analysis

Background

Previous studies have been inconsistent with respect to the reported associations between human epidermal growth factor receptor (HER-2/neu) overexpression in colorectal cancer. The aims of this meta-analysis are to assess its correlation with clinicopathological characteristics and prognostic significance in colorectal cancer.

Methods

Eligible studies were searched in Pubmed, Embase and Web of Science databases. The inclusion criteria were studies that assessed the relationship between HER-2 expression detected by immunohistochemistry (IHC) and the prognosis or clinicopathological features in patients with colorectal cancer (CRC). Subgroup analysis according to sex, tumor location, TNM stage, grade of differentiation and lymph node metastasis were produced. Odds ratio (OR) or hazard ratio (HR) with 95 % confidence interval (CI) were calculated to examine the risk or hazard association, and heterogeneity and publication bias analyses were also performed.

Results

A total of 18 studies comprising 2867 colorectal cancer patients were included to assess the association between HER-2 immunohistochemical expression and clinicopathological characteristics and survival. The overall analysis showed that there was no detectable relation between HER-2 expression and prognosis in colorectal cancer patients with the pooled HR of 1.08 (95 % CI: 0.96–1.21, P = 0.21). With respect to clinicopathological features, there was also no detectable relation between HER-2 expression and sex (OR = 0.91, 95 % CI: 0.72–1.15, P = 0.42), tumor location (OR = 1.21, 95 % CI = 0.88–1.65, P = 0.24), grade of differentiation (OR = 1.03, 95 % CI = 0.72–1.47, P = 0.86), TNM stages (OR = 0.72, 95 % CI = 0.31–1.66, P = 0.44), or lymph node metastasis (OR = 1.90, 95 % CI = 0.90–4.02, P = 0.09) in CRC.

Conclusions

The finding from this present meta-analysis suggested that HER-2 overexpression was not related to clinicopathological characteristics and poor prognostic of colorectal cancer patients.

Lack of effects of HER-2/neu on prognosis in colorectal cancer: a meta-analysis

BACKGROUND

The prognostic value of human epidermal growth factor receptor-2 (HER-2/neu) for survival of patients with colorectal cancer (CRC) is still ambiguous. We therefore performed a meta-analysis to evaluate its prognostic significance.

MATERIALS AND METHODS

We searched the MEDLINE and EMBASE databases for published literature investigating associations between HER-2/neu status and overall survival of patients with CRC. A meta-analysis was performed using a DerSimonian-Laird model and publication bias was investigated by Begg's and Egger's tests. Subgroup analysis was also conducted according to the study design type, study quality score, cut-off value for HER-2/neu overexpression, publication region, patient number and publication year.

RESULTS

A total of 17 eligible studies involving 2,347 patients were identified for this meta-analysis. The combined hazard ratio (HR) was 1.31 (95% confidence interval (CI): 0.96-1.79), suggesting that HER-2/neu overexpression was not significantly associated with overall survival of patients with CRC. However, subgroup analysis revealed that HER-2/neu overexpression had an unfavorable impact on survival when the analysis was restricted to subgroups of study quality score ≤ 5 (HR=1.56, 95%CI: 1.17-2.10), Asian patients (HR=1.74, 95%CI: 1.22-2.49), patient number ≤ 106 (HR=1.57, 95%CI: 1.01-2.44), publication year before 2003 (HR=1.59, 95%CI: 1.02-2.49), and prospectively designed study (HR=3.62, 95%CI: 1.42-9.24). The effect disappeared in subgroups of study quality scores > 5 (HR=0.69, 95%CI: 0.33-1.44), non Asian patients (HR=1.14, 95%CI: 0.77-1.70), patients' number > 106 (HR=1.07, 95%CI: 0.67-1.72), publication year after 2003 (HR=1.13, 95%CI: 0.76-1.69), and retrospectively designed study (HR=1.22, 95%CI: 0.89-1.67).

CONCLUSIONS

Our meta-analysis suggests that HER-2/neu overexpression might not be a significantly prognostic indicator for patients with CRC. Further studies are required to confirm these results.

HER-2 overexpression and survival in colorectal cancer: a meta-analysis

OBJECTIVE

Numerous studies examining the relationship between human epidermal growth factor receptor 2 (HER-2) overexpression and survival in patients with colorectal cancer (CRC) have yielded controversial results. We therefore performed a meta-analysis more precisely to estimate its prognostic value.

METHODS

Published studies investigating the effect of HER-2 overexpression on CRC survival were identified; the hazard ratios (HRs) and their corresponding 95% confidence intervals (95% CIs) were pooled in terms of disease-specific or overall survival.

RESULTS

Eleven studies were included in the meta-analysis. The pooled data showed that HER-2 overexpression was negatively related to CRC survival (HR=1.10, 95% CI: 0.77-1.44). Subgroup analyses regarding test method and study quality also demonstrated little association between HER-2 overexpression and CRC survival (HR=0.89, 95% CI: 0.50-1.29; HR=0.90, 95% CI: 0.43-1.37, respectively).

CONCLUSIONS

Regardless of several limitations, our study suggested that HER-2 overexpression probably had little impact on CRC survival.

HER-2 involvement in osteosarcoma

The major goals of translational research in osteosarcoma entail the identification of prognostic factors and therapeutic targets. Given the relevance of epidermal growth factor receptor pathway to breast cancer and the finding that HER-2 was expressed in a proportion of osteosarcoma, it was reasonable to investigate this pathway further. Investigations of HER-2 in osteosarcoma have led to the publication of numerous conflicting reports with regard to the level and prognostic value of HER-2 expression, which are reviewed and discussed. Numerous lessons provided by this research experience are described. This pathway has also been explored as a therapeutic target with at least one study of trastuzumab for the treatment of osteosarcoma completed. Other studies utilizing alternative approaches to target the HER-2 receptor for the treatment of osteosarcoma have been considered.

HER2 status in colorectal cancer: its clinical significance and the relationship between HER2 gene amplification and expression

This study aimed at determining the incidence and clinical implications of HER2 status in primary colorectal cancer (CRC). HER2 status was investigated in two retrospective cohorts of 365 consecutive CRC patients (cohort 1) and 174 advanced CRC patients with synchronous or metachronous distant metastasis (cohort 2). HER2 status was determined by performing dual-color silver in-situ hybridization (SISH), mRNA in-situ hybridization (ISH), and immunohistochemistry (IHC). The incidence of HER2 protein overexpression (IHC 2+/3+) was approximately 6% (22 of 365 in cohort 1; 10 of 174 in cohort 2). HER2 gene amplification was observed in 5.8% of the patients from cohort 1 and 6.3% of the patients from cohort 2. HER2 gene amplification was more frequently observed in CRCs located in the rectum than in the right and left colon (P = 0.013 in cohort 1; P = 0.009 in cohort 2). HER2 status, determined by IHC, ISH, and dual-color SISH, was not significantly associated with aggressive CRC behaviour or patients' prognosis in both the cohorts. Of the combined cohort with a total of 539 cases, the concordance rate was 95.5% between dual-color SISH and IHC detection methods. On excluding equivocally immunostained cases (IHC 2+), the concordance rate was 97.7%. HER2 mRNA overtranscription, detected by ISH, significantly correlated with protein overexpression and gene amplification (P<0.001). HER2 gene amplification was identified in a minority of CRC patients with high concordance rates between dual-color SISH and IHC detection methods. Although HER2 status did not predict patients' prognosis, our findings may serve as a basis for future studies on patient selection for HER2 targeted therapy.

Human epidermal growth factor receptor-2 expression in locally advanced rectal cancer: association with response to neoadjuvant therapy and prognosis

The aim of this study was to determine whether pretreatment status of human epidermal growth factor receptor-2 (HER-2) could predict pathologic response to neoadjuvant chemoradiotherapy (nCRT) and outcomes for patients with locally advanced rectal cancer (LARC). A total of 119 patients diagnosed with LARC received standardized multimodal treatment. Their HER-2 status was determined in pretreatment biopsies by immunohistochemistry (IHC) and FISH. Tumor response was assessed in resected regimens using the tumor regression grade system and TNM staging system. Twenty-two cases in 119 patients assessed as IHC3+ or IHC2+ plus gene-amplified were determined as HER-2 positive. Positive HER-2 status was not associated with any pretreatment clinicopathologic parameters (P > 0.05). HER-2 status could not predict pathologic response to nCRT based on downstaging (P = 0.210) and tumor regression grade (P = 0.085) but it provides us with a trend that HER-2-positive tumors may be resistant to nCRT. Positive HER-2 status was significantly associated with poor 5-year disease-free survival (P = 0.015) and 5-year overall survival (P = 0.026). It can act as a worse prognostic factor for LARC patients.

Expression of HER-2 in rectal cancers treated with preoperative radiotherapy: a potential biomarker predictive of metastasis

BACKGROUND

Evidence suggests HER-2 overexpression may be predictive of prognosis in colorectal cancer patients, though this remains controversial.

OBJECTIVES

This study was performed to assess the prognostic value of HER-2 expression in locally advanced rectal cancer patients after preoperative radiotherapy.

PATIENTS AND METHODS

HER-2 expression was evaluated based on immunohistochemical (IHC) staining of resected specimens from 142 mid-to-low rectal cancer patients. Fluorescence in situ hybridization (FISH) was performed to confirm HER-2 overexpression in samples with an IHC score of 2+. Tumor regression grading (TRG) of the primary tumors was determined semiquantitatively using a tumor regression grading scheme advocated in the AJCC Cancer Staging Manual 7 edition.

RESULTS

When the total staining intensity was evaluated, 106 samples (74.6%) showed barely-perceptible positivity (0-1+; HER-2--negative), 15 samples (10.6%) showed moderate positivity (2+) and 21 samples (14.8%) showed strong positivity (3+, HER-2 positive). FISH confirmed that 2 cases showing moderate HER-2 positivity (2+) overexpressed HER2. There was no significant difference between the HER-2 positive and -negative groups with respect to age, gender, TRG, TNM stage, downstaging status, lymphovascular invasion or tumor differentiation. A significant correlation was found between HER-2 overexpression and the incidence of distant metastasis (p = 0.005). Subgroup analysis revealed this correlation was not significant (p = 0.247) in the radiation-insensitive (TRG0-2) subgroup, whereas a significant correlation (p = 0.026) between HER-2 overexpression and distant metastasis was found in the radiation-resistant (TRG3) subgroup. Multivariate analysis identified ypN stage (OR = 0.473, p = 0.002)and overexpression of HER-2 (OR = 3.704, p = 0.008) as independent risk factors for distant metastasis. There was no correlation between HER-2 overexpression and disease-free survival or overall survival among the study population.

LIMITATIONS

We reported that HER-2 overexpression was correlated with distant metastasis in rectal cancer patients, especially in the radiation-insensitive group. However, there are certain limitations. First, this study was limited due to the fact that the number of rectal patients enrolled was only 142, which is relatively small. Second, HER-2 expression was measured by IHC with a positive ratio around 15%, which is fairly high according to the literature. Also, we collected the tissue samples preoperatively. It would be interesting to know the HER-2 expression levels pre- and postradiotherapy, as well as their correlation with local recurrence or distant metastasis. Finally, in rectal cancer patients, there is little information published on HER-2 and its role in tumor progression and metastasis. Therefore, we are pursuing the regulatory molecule underlined.

CONCLUSIONS

HER-2 is overexpressed in around 15% of rectal cancer patients who receive neoadjuvant radiotherapy. Moreover, HER-2 overexpression could be a predictive biomarker of distant metastasis in rectal cancer patients after preoperative radiotherapy, especially patients showing a poor response to neoadjuvant radiotherapy.

Death decoy receptor overexpression and increased malignancy risk in colorectal cancer

AIM: To evaluate human epidermal growth factor receptor 2 (HER2) and death decoy receptor (DcR3) as colorectal cancer prognostic indicators.

METHODS: Colorectal carcinoma specimens from 300 patients were analyzed by immunohistochemistry to detect the staining patterns of HER2 and DcR3. Classification of HER2 staining was carried out using the United States Food and Drug Administration semi-quantitative scoring system, with scores of 0 or 1+ indicating a tumor-negative (normal expression) status and scores of 2+ and 3+ indicating a tumor-positive (overexpression) status. Classification of DcR3 was carried out by quantitating the percentage of positive cells within the stained section, with < 10% indicating a tumor-negative status and ≥ 10% indicating a tumor-positive status. Correlation of the HER2 and DcR3 staining status with clinicopathological parameters [age, sex, tumor size, differentiation, and the tumor, node, metastasis (pTNM) classification] and survival was statistically assessed.

RESULTS: Tumor-positive status for HER2 and DcR3 was found in 18.33% and 58.33% of the 300 colorectal carcinoma specimens, respectively. HER2 tumor-positive status showed a significant correlation with tumor size (P = 0.003) but not with other clinicopathological parameters. DcR3 tumor-positive status showed a significant correlation with tumor differentiation (P < 0.001), pTNM stage (P < 0.001), and lymph node metastasis (P < 0.001). However, correlation coefficient analysis did not indicate that a statistically significant correlation exists between tumor-positive status for the HER2 and DcR3 overexpression (P = 0.236). Patients with specimens classified as DcR3-overexpressing had a significantly worse overall survival (OS) rate than those without DcR3 overexpression (median OS: 42.11 vs 61.21 mo; HR = 50.27, 95%CI: 44.90-55.64, P < 0.001). HER2 overexpression had no significant impact on median OS (35.10 mo vs 45.25 mo; HR = 44.40, 95%CI: 39.32-49.48, P = 0.344). However, patients with specimens classified as both HER2- and DcR3-overexpressing had a significantly poorer median OS than those with only HER2 overexpression (31.80 mo vs 52.20 mo; HR = 35.10, 95%CI: 22.04-48.16, P = 0.006).

CONCLUSION: HER2 overexpression is not an independent prognostic marker of colorectal cancer, but DcR3 overexpression is highly correlated with lymph node metastasis and poor OS.

Comparison of HER2 expression between primary colorectal cancer and their corresponding metastases

The aim of this study was to compare human epidermal growth factor 2 (HER2) status in primary colorectal cancer and paired liver or lung metastasis. Gene amplification of HER2 has been intensively evaluated in contemporary oncology, especially in breast and stomach cancer. The knowledge of HER2 status in primary and metastatic sites may be of potential value for therapeutic decision making in metastatic colon cancer. The HER2 status was assessed by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) in 94 colorectal cancer with corresponding liver or lung metastases. HER2 amplification was present in 19 of the 188 (10.1%) of both primary and metastases combined. Four (4.6%) patients showed HER2 amplification in the metastasis and 10 (10.6%) patients showed HER2 amplification in the primary tumor. In 14 cases (14.8%), the HER2 status of the primary lesions was different from that of the associated metastases. The presence of HER2 overexpression in KRAS mutant colon cancer was found in 5.3%. No relationship was found between HER2 expression and KRAS status (P = 0.486). The evidence of HER2 positive metastatic lesion and primary colorectal cancer suggest that HER2 assessment might be considered in selected cases when this may help change the therapeutic decision.

Over-expression of Her-2 in colorectal cancer tissue, but not in serum, constitutes an independent worse prognostic factor

BACKGROUND

Currently, conflicting information exists regarding Her-2 over-expression and its clinicopathological implications in colorectal cancer (CRC). This study was undertaken to determine Her-2 over-expression in both serum and tumor tissue of CRC patients, and to assess its clinicopathological and targeted therapeutic implications.

METHODS

Ninety five CRC patients and sixty healthy controls were prospectively enrolled. Her-2 expression status in serum and CRC tissue were examined by chemiluminescent immunoassay and immunohistochemical staining, respectively. The results were confirmed using fluorescent in situ hybridization. Clinicopathological parameters were analyzed according to Her-2 expression status.

RESULTS

Serum Her-2 levels were found to be increased in CRC patients as compared to those of healthy controls. However, serum Her-2 levels were not found to be significantly associated with prognostic parameters. Her-2 expression analysis of CRC tissues revealed Her-2 over-expression in 23 patients (25%), i.e., 13 patients (14%) showed moderate over-expression and 10 patients (11%) showed strong over-expression. The overall survival of patients negative for Her-2 expression was significantly better than that of patients positive for Her-2 expression (P=0.018). The disease-free survival of patients with Her-2 over-expression was significantly shorter than that of patients with no Her-2 expression (P=0.021).

CONCLUSIONS

Her-2 over-expression in CRC tissue, but not in serum, acts as a significant independent worse prognostic factor. Assessment of Her-2 expression status may be valuable for the targeted therapeutic management of CRC.

Cytoplasmic Overexpression of HER2: a Key Factor in Colorectal Cancer

Trastuzumab, a humanized mouse monoclonal antibody directed against HER2 (Human Epidermal Growth Factor Receptor 2), is currently a keystone in the treatment of breast cancer. Meanwhile, trastuzumab has been validated for use in other types of cancer too. But the data on HER2 expression in colorectal cancer are ambiguous, with reported overexpression of HER2 varying between zero and 84%. In this review these studies are evaluated and compared. It shows that many factors influence the determination of HER2-expression, especially of the intracellular fraction of HER2. It is concluded that although membranous overexpression of HER2 is low in colorectal cancer with only 5% of all patients being positive, a significant proportion of the patients (30%) shows cytoplasmic HER2 overexpression. The clinical impact of enhanced intracellular HER2 is not known, because the nature and origin have not completely been revealed yet. Enlightening this process could be a stepping stone towards targeting of intracellular HER2 as a treatment option.

HER-2 Expression in Brain Metastases from Colorectal Cancer and Corresponding Primary Tumors: A Case Cohort Series

Brain metastases (BM) from colorectal cancer (CRC) are a rare but increasing event. Surgical resection of oligometastatic disease, including BM, may produce a survival benefit in selected patients. Previous studies described the HER-2 expression patterns in CRC patients, but its prognostic role still remains controversial. Information on the HER-2 expression in BM from CRC is currently lacking. Among the over 500 patients treated at our Department of Neurosurgery in the last 13 years (1999–2012), we identified a cohort of 50 consecutive CRC patients resected for BM. Clinical data were retrospectively reviewed using electronic hospital charts and surgical notes. Formalin-fixed, paraffin-embedded tissue samples were retrieved and histologically reviewed. HER-2 status was assessed on 4-μm sections by HerceptTest™, and scored by two pathologists according to gastric cancer HER-2 status guidelines. In score 2+ cases HER-2 gene copy number was analyzed by FISH, performed using the PathVysion HER-2 DNA Probe Kit. Median age at time of BM resection was 65 years (35–82); most patients were males (60%) with a good performance status. The majority of the BM were single (74%) and sited in the supratentorial area (64%); 2–4 lesions were diagnosed in 9 patients (18%), and >4 in 3 patients (6%). The rate of HER-2 positivity (defined as IHC score 3+ or IHC score 2+ and FISH gene amplification) was 8.1% for the primary CRC tumors and 12% for their corresponding BM. The concordance rate between primary tumors and matched BM was 89%. Median overall survival after neurosurgery was 6.5 months for HER-2 IHC score 0 vs. 4.6 months for HER-2 IHC score 1+/2+/3+; the difference was statistically significant (p = 0.01, Log-rank test). HER-2 positivity of our case cohort was low but comparable to literature. Concordance rate of HER-2 expression between BM and corresponding primary tumors is high and similar to those reported for breast and gastric cancers. Our data suggest a potential negative prognostic value of HER-2 expression in brain lesions from CRC.

Membranous expression of Her3 is associated with a decreased survival in head and neck squamous cell carcinoma

Background

Head and neck squamous cell carcinoma (HNSCC) still remains a lethal malignancy benefiting from the identification of the new target for early detection and/or development of new therapeutic regimens based on a better understanding of the biological mechanism for treatment. The overexpression of Her2 and Her3 receptors have been identified in various solid tumors, but its prognostic relevance in HNSCC remains controversial.

Methods

Three hundred eighty-seven primary HNSCCs, 20 matching metasis and 17 recurrent HNSCCs were arrayed into tissue microarrays. The relationships between Her2 and Her3 protein expression and clinicopathological parameters/survival of HNSCC patients were analyzed with immunohistochemistry.

Results

Her3 is detected as either a cytoplasmic or a membranous dominant expression pattern whereas Her2 expression showed uniform membranous form. In primary tumor tissues, high membranous Her2 expression level was found in 104 (26.9%) cases while positive membranous and cytoplasmic Her3 expression was observed in 34 (8.8%) and 300 (77.5%) samples, respectively. Membranous Her2 expression was significantly associated with histological grade (P = 0.021), as grade 2 tumors showed the highest positive expression. Membranous Her3 over-expression was significantly prevalent in metastatic tissues compared to primary tumors (P = 0.003). Survival analysis indicates that membranous Her3 expression is significantly associated with worse overall survival (P = 0.027) and is an independent prognostic factor in multivariate analysis (hazard ratio, 1.51; 95% confidence interval, 1.01-2.23; P = 0.040).

Conclusions

These results suggest that membranous Her3 expression is strongly associated with poor prognosis of patients with HNSCC and is a potential candidate molecule for targeted therapy.

Clinicopathological and prognostic significance of HER-2/neu and VEGF expression in colon carcinomas

BACKGROUND

HER-2/neu and VEGF expression is correlated with disease behaviors in various cancers. However, evidence for their expression in colon cancer is rather contradictory both for the protein expression status and prognostic value. HER-2/neu is found to participate in VEGF regulation, and has known correlation with VEGF expression in some tumors. In this study, we investigated HER-2/neu and VEGF expression in Chinese colon patients and explored whether there was any correlation between their expression patterns.

METHODS

HER-2/neu and VEGF were investigated immunohistochemically using tumor samples obtained from 317 colon cancer patients with all tumor stages. Correlation of the degree of staining with clinicopathological parameters and survival was investigated.

RESULTS

Positive expression rates of HER-2/neu and VEGF in colon cancer were 15.5% and 55.5% respectively. HER-2/neu expression was significantly correlated with tumor size and distant metastases (P < 0.05), but was not an independent prognostic marker of survival (P > 0.05). Expression of VEGF was significantly correlated with tumor size, tumor stage, lymph node metastases, and distant metastases (P < 0.05). The 5-year survival rate in patients with negative and positive VEGF expression was 70.2% and 61.9% respectively; the difference was not statistically significant (P = 0.146). No correlation between HER-2/neu and VEGF expression was detected (P = 0.151).

CONCLUSIONS

HER-2/neu and VEGF are not important prognostic markers of colon cancer. The present results do not support any association between HER2/neu and VEGF expression in this setting.

Predictive markers of colorectal cancer liver metastases

Liver metastases are the most common site of distant failure after curative resection of colorectal cancer and a source of significant cancer-related morbidity and mortality. Currently, imaging and conventional histopathologic features, such as T-stage and N-stage, are used by clinicians to inform prognosis and guide adjuvant treatment to reduce the risk of developing distant metastases. However, these tools only have a moderate ability to predict the development of liver metastases. Novel methods, including the detection of circulating tumor cells and carcinoembryonic antigens in serum, have been developed, and their prognostic and predictive characteristics have been assessed. In addition, several molecular and genetic markers in the primary tumor have been studied. Unfortunately, these studies are often small and their results have been mixed, yielding no consistent sets of externally validated predictors of colorectal liver metastases. For widespread clinical relevance, future tests need to be independently carried out on large independent patient samples.

Cell surface markers in colorectal cancer prognosis

The classification of colorectal cancers (CRC) is currently based largely on histologically determined tumour characteristics, such as differentiation status and tumour stage, i.e., depth of tumour invasion, involvement of regional lymph nodes and the occurrence of metastatic spread to other organs. These are the conventional prognostic factors for patient survival and often determine the requirement for adjuvant therapy after surgical resection of the primary tumour. However, patients with the same CRC stage can have very different disease-related outcomes. For some, surgical removal of early-stage tumours leads to full recovery, while for others, disease recurrence and metastasis may occur regardless of adjuvant therapy. It is therefore important to understand the molecular processes that lead to disease progression and metastasis and to find more reliable prognostic markers and novel targets for therapy. This review focuses on cell surface proteins that correlate with tumour progression, metastasis and patient outcome, and discusses some of the challenges in finding prognostic protein markers in CRC.