Multicenter phase II and translational study of cetuximab in metastatic colorectal carcinoma refractory to irinotecan, oxaliplatin, and fluoropyrimidines

Dermatology-related quality-of-life outcomes in patients with RAS wild-type metastatic colorectal cancer treated with fluorouracil and folinic acid with or without panitumumab (Pmab) maintenance after FOLFOX + Pmab induction: a prespecified secondary analysis of the phase II randomized PanaMa (AIO KRK 0212) trial

BACKGROUND

The key endpoints for the assessment of the effect of maintenance therapy for metastatic colorectal cancer (mCRC) are survival and quality-of-life outcomes. We aimed to compare dermatology-related quality of life (DRQOL) in patients with RAS wild-type (wt) mCRC treated with fluorouracil and folinic acid (FU/FA) + panitumumab (Pmab) versus FU/FA alone as maintenance therapy after folinic acid, fluorouracil and oxaliplatin + Pmab induction.

PATIENTS AND METHODS

The phase II randomized PanaMa (AIO KRK 0212; NCT01991873) trial included 387 patients at 70 community/academic sites in Germany. For this prespecified secondary analysis, DRQOL outcomes were assessed using the Functional Assessment of Cancer Therapy-epidermal growth factor receptor inhibitor (FACT-EGFRI), Dermatology Life Quality Index (DLQI), and Skindex-16 questionnaires at every second cycle of therapy until disease progression/death.

RESULTS

At least one DRQOL questionnaire was completed by a total of 310/377 (82%) patients who received induction therapy, and by 216/248 (87%) patients who were randomized and received maintenance therapy. Patients who experienced skin toxicity according to the National Cancer Institute (NCI)-Common Terminology Criteria for Adverse Events (CTCAE) during induction therapy had significantly worse DRQOL according to all three measures, compared to those who did not [i.e. Skindex-16, mean difference at cycle 2 -12.87; 95% confidence interval (CI) -20.01 to -5.73; P < 0.001]. During maintenance therapy, significantly improved recovery was observed in all DRQOL measures for patients receiving FU/FA, compared to those receiving additional Pmab (i.e. Skindex-16, mean difference at cycle 6 -16.53; 95% CI -22.68 to -10.38; P < 0.001).

CONCLUSIONS

In this secondary analysis of a phase II randomized clinical trial, patient-reported DRQOL outcomes correlated with skin toxicity according to NCI-CTCAE during induction therapy. Maintenance therapy with FU/FA + Pmab was associated with deteriorated DRQOL versus FU/FA alone in patients with RAS wt mCRC.

Efficacy and safety of adapalene gel as a reactive treatment for cetuximab-induced skin toxicity in recurrent or metastatic squamous cell carcinoma of the head and neck: A historical cohort comparison study

INTRODUCTION

Despite the common occurrence of cetuximab (Cmab)-induced skin toxicity, management strategies are not well established. The traditional mainstay method consists of topical steroids, which, if used excessively, may give rise to other concerns. Alternatively, adapalene can activate epidermal growth factor receptor pathways to potentially alleviate these toxicities.

METHODS

We prospectively studied 31 patients with recurrent or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN) who were eligible to use adapalene gel as a reactive treatment for topical steroid-refractory skin toxicity. For comparison, we retrospectively reviewed 99 patients with R/M SCCHN (historical control cohort) whose skin toxicity was mainly treated with topical steroids. We compared the frequency and severity of Cmab-induced skin toxicity, Cmab therapy status (e.g., dose modification), side effects caused by topical steroids and adapalene gel itself, and other medical interventions.

RESULTS

Adapalene gel was used by eight patients (25.8%) in the prospective cohort. Patients in the historical control cohort more frequently required escalation of topical steroid potency (34.3% vs. 12.9%, p = 0.022). Although there was no statistically significant difference in the frequency of grade ≥3 facial skin rash and paronychia between the two cohorts, the prospective cohort showed a significantly shorter time to complete recovery from grade 2/3 paronychia (16 vs. 47 days, p = 0.017). Further, while no skin infections were observed in the prospective cohort, 13 patients in the historical control cohort developed skin infections, especially periungual infection (0% vs. 13.1%, p = 0.024). In addition, no patients in the prospective cohort received a dose reduction of Cmab due to skin toxicities, compared to 20 patients in the historical control cohort (0% vs. 20.2%, p = 0.003). No apparent adapalene gel-related side effects were observed.

CONCLUSIONS

Adapalene gel may be an effective management option for topical steroid-refractory Cmab-induced skin toxicities and could improve compliance with Cmab therapy.

Ibrutinib combination therapy for advanced gastrointestinal and genitourinary tumours: results from a phase 1b/2 study

BACKGROUND

Ibrutinib, a first-in-class inhibitor of Bruton's tyrosine kinase, is approved for the treatment of various B-cell malignancies and chronic graft-versus-host disease. Based on encouraging preclinical data, safety and efficacy of ibrutinib combined with companion drugs for advanced renal cell carcinoma (RCC), gastric/gastroesophageal junctional adenocarcinoma (GC), and colorectal adenocarcinoma (CRC) were evaluated.

METHODS

Ibrutinib 560 mg or 840 mg once daily was administered with standard doses of everolimus for RCC, docetaxel for GC, and cetuximab for CRC. Endpoints included determination of the recommended phase 2 dose (RP2D) of ibrutinib in phase 1b and efficacy (overall response rate [ORR] for GC and CRC; progression-free survival [PFS] for CRC) in phase 2.

RESULTS

A total of 39 (RCC), 46 (GC), and 50 (RCC) patients were enrolled and received the RP2D. Safety profiles were consistent with the individual agents used in the study. Confirmed ORRs were 3% (RCC), 21% (GC), and 19% (CRC). Median (90% CI) PFS was 5.6 (3.9-7.5) months in RCC, 4.0 (2.7-4.2) months in GC, and 5.4 (4.1-5.8) months in CRC.

CONCLUSIONS

Clinically meaningful increases in efficacy were not observed compared to historical controls; however, the data may warrant further evaluation of ibrutinib combinations in other solid tumours.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02599324.

Downregulation of AC092894.1 promotes oxaliplatin resistance in colorectal cancer via the USP3/AR/RASGRP3 axis

BACKGROUND

Oxaliplatin resistance is a complex process and has been one of the most disadvantageous factors and indeed a confrontation in the procedure of colorectal cancer. Recently, long non-coding RNAs (lncRNAs) have emerged as novel molecules for the treatment of chemoresistance, but the specific molecular mechanisms mediated by them are poorly understood.

METHODS

The lncRNAs associated with oxaliplatin resistance were screened by microarray. lncRNA effects on oxaliplatin chemoresistance were then verified by gain- and loss-of-function experiments. Finally, the potential mechanism of AC092894.1 was explored by RNA pull-down, RIP, and Co-IP experiments.

RESULTS

AC092894.1 representation has been demonstrated to be drastically downregulated throughout oxaliplatin-induced drug-resistant CRC cells. In vivo and in vitro experiments revealed that AC092894.1 functions to reverse chemoresistance. Studies on the mechanism suggested that AC092894.1 served as a scaffold molecule that mediated the de-ubiquitination of AR through USP3, thereby increasing the transcription of RASGRP3. Finally, sustained activation of the MAPK signaling pathway induced apoptosis in CRC cells.

CONCLUSIONS

In conclusion, this study identified AC092894.1 as a suppressor of CRC chemoresistance and revealed the idea that targeting the AC092894.1/USP3/AR/RASGRP3 signaling axis is a novel option for the treatment of oxaliplatin resistance.

Pharmacokinetics and pharmacodynamics of approved monoclonal antibody therapy for colorectal cancer

INTRODUCTION

The introduction of monoclonal antibodies to the chemotherapy backbone treatment has challenged the paradigm of metastatic colorectal cancer (mCRC) treatment. Their mechanism of action and pharmacokinetics are complex but important to understand in order to improve patient selection and treatment outcomes for mCRC population.

AREAS COVERED

This review examines the scientific data, pharmacodynamics, and pharmacokinetics of approved monoclonal antibodies used to treat mCRC patients, including agents targeting signaling via VEGFR (bevacizumab and ramucirumab), EGFR (cetuximab and panitumumab), HER2/3 target therapy, and immunotherapy agents such as pembrolizumab or nivolumab. Efficacy and mechanism of action of bispecific antibodies are also covered.

EXPERT OPINION

mCRC is a heterogeneous disease and the optimal selection and sequence of treatments is challenging. Monoclonal antibodies have complex pharmacokinetics and pharmacodynamics, with important interactions between them. The arrival of bioequivalent molecules to the market increases the need for the characterization of pharmacokinetics and pharmacodynamics of classic monoclonal antibodies to reach bioequivalent novel molecules.

Copy Number Alterations as Novel Biomarkers and Therapeutic Targets in Colorectal Cancer

In colorectal cancer, somatic mutations have played an important role as prognostic and predictive biomarkers, with some also functioning as therapeutic targets. Another genetic aberration that has shown significance in colorectal cancer is copy number alterations (CNAs). CNAs occur when a change to the DNA structure propagates gain/amplification or loss/deletion in sections of DNA, which can often lead to changes in protein expression. Multiple techniques have been developed to detect CNAs, including comparative genomic hybridization with microarray, low pass whole genome sequencing, and digital droplet PCR. In this review, we summarize key findings in the literature regarding the role of CNAs in the pathogenesis of colorectal cancer, from adenoma to carcinoma to distant metastasis, and discuss the roles of CNAs as prognostic and predictive biomarkers in colorectal cancer.

Skin Toxicity as Predictor of Survival in Refractory Patients with RAS Wild-Type Metastatic Colorectal Cancer Treated with Cetuximab and Avelumab (CAVE) as Rechallenge Strategy

The single-arm phase II CAVE mCRC trial evaluated the combination of cetuximab plus avelumab as rechallenge strategy in RAS wild-type (WT) metastatic colorectal cancer (mCRC) patients, with clinical response to first-line anti-EGFR-based chemotherapy, who progressed and received a subsequent line of therapy. The correlation of skin toxicity (ST) and different clinico-molecular variables with overall survival (OS), progression-free survival (PFS) and response rate (RR) was assessed at univariate and multivariate analysis. A total of 33/77 (42.9%) patients experienced grade 2-3 ST and displayed median OS (mOS) of 17.8 months (CI 95%, 14.9-20.6); whereas 44/77 (57.1%) patients with grade 0-1 ST exhibited mOS of 8.2 months (CI 95%, 5.5-10.9), (hazard ratio (HR), 0.51; CI 95%, 0.29-0.89; p = 0.019). Median PFS (mPFS) was 4.6 months (CI 95%, 3.4-5.7) in patients with grade 2-3 ST, compared to patients with grade 0-1 ST with mPFS of 3.4 months (CI 95%, 2.7-4.1; HR, 0.49; CI 95%, 0.3-0.8; p = 0.004). Grade 2-3 ST (HR, 0.51; CI 95%, 0.29-0.89; p = 0.019) and RAS/BRAF/EGFR WT circulating tumor DNA (ctDNA) (HR, 0.50; CI 95%, 0.27-0.9; p = 0.019) had a statistically significant effect on OS at univariate analysis. At the multivariate analysis, RAS/BRAF/EGFR WT ctDNA status maintained statistical significance (HR, 0.49; CI 95%, 0.27-0.9; p = 0.023), whereas there was a trend towards ST grade 2-3 (HR, 0.54; CI 95%, 0.29-1.01; p = 0.054). Skin toxicity is a promising biomarker to identify patients with mCRC that could benefit of anti-EGFR rechallenge.

Lnc-RP11-536 K7.3/SOX2/HIF-1α signaling axis regulates oxaliplatin resistance in patient-derived colorectal cancer organoids

Background

Resistance to oxaliplatin is a major obstacle for the management of locally advanced and metastatic colon cancer (CC). Although long noncoding RNAs (lncRNAs) play key roles in CC, the relationships between lncRNAs and resistance to oxaliplatin have been poorly understood yet.

Methods

Chemo-sensitive and chemo-resistant organoids were established from colon cancer tissues of the oxaliplatin-sensitive or -resistant patients. Analysis of the patient cohort indicated that lnc-RP11-536 K7.3 had a potential oncogenic role in CC. Further, a series of functional in vitro and in vivo experiments were conducted to assess the effects of lnc-RP11-536 K7.3 on CC proliferation, glycolysis, and angiogenesis. RNA pull-down assay, luciferase reporter and fluorescent in situ hybridization assays were used to confirm the interactions between lnc-RP11-536 K7.3, SOX2 and their downstream target HIF-1α.

Results

In this study, we identified a novel lncRNA, lnc-RP11-536 K7.3, was associated with resistance to oxaliplatin and predicted a poor survival. Knockout of lnc-RP11-536 K7.3 inhibited the proliferation, glycolysis, and angiogenesis, whereas enhanced chemosensitivity in chemo-resistant organoids and CC cells both in vitro and in vivo. Furthermore, we found that lnc-RP11-536 K7.3 recruited SOX2 to transcriptionally activate USP7 mRNA expression. The accumulative USP7 resulted in deubiquitylation and stabilization of HIF-1α, thereby facilitating resistance to oxaliplatin.

Conclusion

In conclusion, our findings indicated that lnc-RP11-536 K7.3 could promote proliferation, glycolysis, angiogenesis, and chemo-resistance in CC by SOX2/USP7/HIF-1α signaling axis. This revealed a new insight into how lncRNA could regulate chemosensitivity and provide a potential therapeutic target for reversing resistance to oxaliplatin in the management of CC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02143-x.

Phase II Trial of Trametinib and Panitumumab in RAS/RAF Wild Type Metastatic Colorectal Cancer

INTRODUCTION

MEK inhibition may overcome resistance to EGFR inhibition in patients with RAS wildtype (wt) metastatic colorectal cancer (mCRC). We evaluated antitumor activity of trametinib (MEK1/2 inhibitor) with panitumumab (EGFR monoclonal antibody) in a phase II trial.

METHODS

Patients with KRAS, NRAS, and BRAF wt mCRC with prior 5-FU, irinotecan, oxaliplatin, +/- bevacizumab and no prior anti-EGFR therapy were treated with trametinib 1.5 mg oral daily and panitumumab 4.8 mg/kg IV every 2 weeks. Primary endpoint was clinical benefit rate (CB; CR, PR, or SD ≥24 weeks) by RECIST v1.1. A 2-stage minimax design was used. Serial plasma circulating free DNA (cfDNA) was collected and profiled using Oncomine Lung cfDNA assay.

RESULTS

Fourteen patients were enrolled from November 2015 to April 2019. CB rate was 38% (5/13) and median progression free survival (PFS) was 4.4 months (95% CI, 2.9-7.1). Confirmed overall response rate was 38% (5/13). Treatment-related AE (trAE) included acneiform rash (85%), diarrhea (62%), maculopapular rash (54%), mucositis (46%), and others. Dose modifications and interruptions of trametinib occurred in 69% and panitumumab in 54% of patients. The trial did not progress to stage II accrual due to tolerability and short duration of response. RAS or BRAF mutations cfDNA were detected in 3/13 patients (23%) before radiographic disease progression.

CONCLUSION

The addition of trametinib to panitumumab led to a high rate of tumor shrinkage in RAS/RAF wt metastatic colorectal cancer, with poor tolerability due to a high incidence of skin toxicity. Median PFS was similar to panitumumab alone in historical control data.

Clinical Significance of has_circ_0055625 in Colon Cancer Patients Undergoing FOLFOX Chemotherapy Treatment

Objective

Colon cancer is a leading global cancer-related cause of morbidity and mortality. The oxaliplatin, 5-fluorouracil (5-FU), and leucovorin (FOLFOX) regimen is a standard chemotherapeutic approach used to treat colon cancer. However, chemoresistant tumor cells typically lead to the emergence of recurrent FOLFOX-resistant tumors after initial treatment. As such, it is vital that novel approaches to identifying and eliminating such chemoresistant tumors be developed in an effort to improve patient chemotherapy outcomes.

Materials and Methods

In total, 100 samples of serum were obtained between April 2014 and April 2019 from patients who had been pathologically diagnosed with colon cancer from the Xiamen Haicang Hospital, and after these patients received FOLFOX chemotherapy treatment, serum samples were collected again. The expression of has_circ_0055625 in these serum samples was assessed via qPCR. Additionally, 5-FU IC50 values were detected via CCK-8 assay.

Results

We found has_circ_0055625 to be significantly upregulated in colon cancer patient serum. After FOLFOX treatment, chemotherapy-resistance was associated with the upregulation of has_circ_0055625.

Conclusion

In summary, these data may provide a foundation for future studies of chemotherapeutic resistance in patients undergoing FOLFOX treatment, potentially guiding treatment adjustment strategies. However, further work will be necessary to expand upon these findings.

Polymorphisms within Immune Regulatory Pathways Predict Cetuximab Efficacy and Survival in Metastatic Colorectal Cancer Patients

Cetuximab, an IgG1 EGFR-directed antibody, promotes antibody-dependent cell-mediated cytotoxicity. We hypothesized that single-nucleotide polymorphisms (SNPs) in immune regulatory pathways may predict outcomes in patients with metastatic colorectal cancer treated with cetuximab-based regimens. A total of 924 patients were included: 105 received cetuximab in IMCL-0144 and cetuximab/irinotecan in GONO-ASL608LIOM01 (training cohort), 225 FOLFIRI/cetuximab in FIRE-3 (validation cohort 1), 74 oxaliplatin/cetuximab regimens in JACCRO CC-05/06 (validation cohort 2), and 520 FOLFIRI/bevacizumab in FIRE-3 and TRIBE (control cohorts). Twelve SNPs in five genes (IDO1; PD-L1; PD-1; CTLA-4; CD24) were evaluated by PCR-based direct sequencing. We analyzed associations between genotype and clinical outcomes. In the training cohort; patients with the CD24 rs52812045 A/A genotype had a significantly shorter median PFS and OS than those with the G/G genotype (PFS 1.3 vs. 3.6 months; OS 2.3 vs. 7.8 months) in univariate (PFS HR 3.62; p = 0.001; OS HR 3.27; p = 0.0004) and multivariate (PFS HR 3.18; p = 0.009; OS HR 4.93; p = 0.001) analyses. Similarly; any A allele carriers in the JACCRO validation cohort had a significantly shorter PFS than G/G carriers (9.2 vs. 11.8 months; univariate HR 1.90; p = 0.011; multivariate HR 2.12; p = 0.018). These associations were not demonstrated in the control cohorts. CD24 genetic variants may help select patients with metastatic colorectal cancer most likely to benefit from cetuximab-based therapy.

Hyperphosphatemia Secondary to the Selective Fibroblast Growth Factor Receptor 1-3 Inhibitor Infigratinib (BGJ398) Is Associated with Antitumor Efficacy in Fibroblast Growth Factor Receptor 3-altered Advanced/Metastatic Urothelial Carcinoma

BACKGROUND

Infigratinib (BGJ398) is a potent, selective fibroblast growth factor receptor (FGFR) 1-3 inhibitor with significant activity in metastatic urothelial carcinoma (mUC) bearing FGFR3 alterations. It can cause hyperphosphatemia due to the "on-target" class effect of FGFR1 inhibition.

OBJECTIVE

To investigate the relationship between hyperphosphatemia and treatment response in patients with mUC.

INTERVENTION

Oral infigratinib 125 mg/d for 21 d every 28 d.

DESIGN, SETTING, AND PARTICIPANTS

Data from patients treated with infigratinib in a phase I trial with platinum-refractory mUC and activating FGFR3 alterations were retrospectively analyzed for clinical efficacy in relation to serum hyperphosphatemia. The relationship between plasma infigratinib concentration and phosphorous levels was also assessed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Clinical outcomes were compared in groups with/without hyperphosphatemia.

RESULTS AND LIMITATIONS

Of the 67 patients enrolled, 48 (71.6%) had hyperphosphatemia on one or more laboratory tests. Findings in patients with versus without hyperphosphatemia were the following: overall response rate 33.3% (95% confidence interval [CI] 20.4-48.4) versus 5.3% (95% CI 0.1-26.0); disease control rate 75.0% (95% CI 60.4-86.4) versus 36.8% (95% CI 16.3-61.6). This trend was maintained in a 1-mo landmark analysis. Pharmacokinetic/pharmacodynamic analysis showed that serum phosphorus levels and physiologic infigratinib concentrations were correlated positively. Key limitations include retrospective design, lack of comparator, and limited sample size.

CONCLUSIONS

This is the first published study to suggest that hyperphosphatemia caused by FGFR inhibitors, such as infigratinib, can be a surrogate biomarker for treatment response. These findings are consistent with other reported observations and will need to be validated further in a larger prospective trial.

PATIENT SUMMARY

Targeted therapy is a new paradigm in treating bladder cancer. In a study using infigratinib, a drug that targets mutations in a gene called fibroblast growth factor receptor 3 (FGFR3), we found that elevated levels of phosphorous were associated with greater clinical benefit. In the future, these data may help inform treatment strategies.

Adverse cutaneous reactions to chemotherapeutic drugs

Drug reactions resulting from chemotherapy agents are common and frequently affect the skin. Although often benign, a select few of these cutaneous reactions may necessitate immediate changes to the antineoplastic regimens. Given the diversity of chemotherapeutic skin reactions and their complex implications on patient management, an organized conceptual schema is imperative for proper patient care. We evaluate a number of commonly seen chemotherapy-induced skin toxicities organized by pathogenic mechanism and drug class, providing a framework for the identification and categorization of adverse events to prevent unrecognition. Groupings of these reactions include direct cytotoxicity and/or drug accumulation, immunologic hypersensitivity, and aberrant molecular signaling.

Cutaneous Squamous Cell Carcinoma: From Biology to Therapy

Cutaneous squamous cell carcinoma (CSCC) is the second most frequent cancer in humans and its incidence continues to rise. Although CSCC usually display a benign clinical behavior, it can be both locally invasive and metastatic. The signaling pathways involved in CSCC development have given rise to targetable molecules in recent decades. In addition, the high mutational burden and increased risk of CSCC in patients under immunosuppression were part of the rationale for developing the immunotherapy for CSCC that has changed the therapeutic landscape. This review focuses on the molecular basis of CSCC and the current biology-based approaches of targeted therapies and immune checkpoint inhibitors. Another purpose of this review is to explore the landscape of drugs that may induce or contribute to the development of CSCC. Beginning with the pathogenetic basis of these drug-induced CSCCs, we move on to consider potential therapeutic opportunities for overcoming this adverse effect.

Trastuzumab Specific Epitope Evaluation as a Predictive and Prognostic Biomarker in Gastric Cancer Patients

While human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) antibodies bind to the intracellular domain, trastuzumab binds to the extracellular epitope of HER2 receptor: target of drug action. We aimed to evaluate clinical significance of the new IHC method assessing the target of trastuzumab in gastric cancer (GC) patients and compare with conventional methods. Sixty-nine trastuzumab-treated GC patients were enrolled from two different cohorts. Additionally, we enrolled 528 consecutive GC patients to evaluate prognostic implications of HER2 test methods. HER2 status was assessed by trastuzumab IHC, HER2 IHC (4B5), and HER2 silver in situ hybridization (SISH). HER2 IHC showed 3+ in 48/69 trastuzumab-treated patients (69.6%), however, trastuzumab IHC showed 3+ in 25 (36.2%). Patients with trastuzumab IHC ≥2+ had significantly better progression-free survival (PFS) and overall survival (OS) than their counterpart (p = 0.014). In univariate analysis, trastuzumab IHC ≥2+ and HER2 IHC 3+ were only significant predictive factors for OS in trastuzumab-treated patients. Of the 528 consecutive GCs, patients with trastuzumab IHC ≥2+ had shorter disease-free survival (DFS) and OS (p = 0.008 and 0.031, respectively), while conventional methods failed to reveal any significant survival differences. HER2 assessment by trastuzumab IHC was different from conventional HER2 test results. Trastuzumab IHC was suggested to be a significant predictive factor for trastuzumab responsiveness and prognostic factor for consecutive GCs.

Prognostic factors in patients treated with transarterial radioembolization for unresectable and chemorefractory colorectal cancer with liver metastases

Background: Transarterial radioembolization (TARE) is used to treat unresectable colorectal cancer with liver metastases (CRCLM). This study aimed to assess survival after TARE and to identify potential prognostic factors in this patient population. Methods: Patients with unresectable and chemorefractory CRCLM treated with TARE at our institution between February 2006 and September 2015 were included in the study. Survival rate, hepatic tumor response, and potential prognostic factors were analyzed. Results: In the 43 study patients, the mean follow-up was 15.0 ± 14.2 months, with a median survival of 13.0 months and 1-, 2-, 3-, 4-, and 5-year survival rates of 52.1%, 24.9%, 21.4%, 21.4%, and 7.1%, respectively. The mean activity of yttrium-90 administered was 1.55 ± 0.28 GBq for the disease-controlled group and 1.19 ± 0.27 GBq for the progressive disease group (p= 0.031). Survival was correlated with Child-Pugh class (p< 0.001), hepatic tumor response (p= 0.001), and baseline carcinoembryonic antigen (CEA) level (p= 0.013). Conclusion: Child-Pugh class B, low degree of hepatic tumor response, and normal baseline CEA levels are prognostic factors for poorer survival after TARE in patients with unresectable and chemorefractory CRCLM. Hepatic tumor response is related to radiation activity delivered to the liver.

The landscape of genomic copy number alterations in colorectal cancer and their consequences on gene expression levels and disease outcome

Aneuploidy, the unbalanced state of the chromosome content, represents a hallmark of most solid tumors, including colorectal cancer. Such aneuploidies result in tumor specific genomic imbalances, which emerge in premalignant precursor lesions. Moreover, increasing levels of chromosomal instability have been observed in adenocarcinomas and are maintained in distant metastases. A number of studies have systematically integrated copy number alterations with gene expression changes in primary carcinomas, cell lines, and experimental models of aneuploidy. In fact, chromosomal aneuploidies target a number of genes conferring a selective advantage for the metabolism of the cancer cell. Copy number alterations not only have a positive correlation with expression changes of the majority of genes on the altered genomic segment, but also have effects on the transcriptional levels of genes genome-wide. Finally, copy number alterations have been associated with disease outcome; nevertheless, the translational applicability in clinical practice requires further studies. Here, we (i) review the spectrum of genetic alterations that lead to colorectal cancer, (ii) describe the most frequent copy number alterations at different stages of colorectal carcinogenesis, (iii) exemplify their positive correlation with gene expression levels, and (iv) discuss copy number alterations that are potentially involved in disease outcome of individual patients.

Correlation between adverse events after drug treatment and the MDR1 C3435T polymorphism in advanced non-small cell lung cancer patients in an Asian population: a meta-analysis

Objective

To determine the association between the multidrug resistance 1 gene ( MDR1) C3435T polymorphism and adverse drug reactions in advanced non-small cell lung cancer (NSCLC) patients in Asia.

Methods

Literature about the relationship between the MDR1 C3435T polymorphism and adverse drug reactions in advanced NSCLC patients were collected from three English language databases (PubMed, Cochrane, and Embase) as well as three Chinese databases (Wanfang, China Knowledge Network, and the Chinese Biomedical Literature Database), and summarized by a meta-analysis.

Results

NSCLC patients with the T allele or TT genotype were significantly more likely to experience diarrhea than those with other genotypes under the allele model (odds ratio [OR] = 1.64, 95% confidence interval [CI]: 1.04–2.61), homozygous model (OR = 3.87, 95% CI: 1.49–10.07), and recessive model (OR = 4.48, 95% CI: 1.88–10.68). Similarly, these patients were significantly more likely to experience skin rash under the allele model (OR = 2.41, 95% CI: 1.24–4.66), homozygous model (OR = 4.77, 95% CI: 1.13–20.15), and dominant model (OR = 1.77, 95% CI: 1.03–3.05).

Conclusions

Asian NSCLC patients with the MDR1 C3435T T allele or TT genotype are significantly more likely to develop diarrhea and rash after drug treatment.

Synthesis and evaluation of 64Cu-radiolabeled NOTA-cetuximab (64Cu-NOTA-C225) for immuno-PET imaging of EGFR expression

Objective

Epidermal growth factor receptor (EGFR) is overexpressed in a wide variety of solid tumors, serving as a well-characterized target for cancer imaging or therapy. In this study, we aimed to design and synthesize a radiotracer, ⁶⁴Cu-NOTA-C225, targeting EGFR for tumor positron emission tomography (PET) imaging.

Methods

Cetuximab (C225) was conjugated to a bifunctional chelator, p-isothiocyanatobenzyl-1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA), and further radiolabeled with copper-64 for PET imaging. ⁶⁴Cu-NOTA-IgG and Cy5.5-C225 were also synthesized as control probes. A431 and A549 mouse models were established for micro-PET and/or near-infrared fluorescence (NIRF) imaging.

Results

⁶⁴Cu-NOTA-C225 exhibited stability in vivo and in vitro up to 24 h and 50 h post-injection, respectively. A431 tumors with average standard uptake values (SUVs) of 5.61±0.69, 6.68±1.14, 7.80±1.51 at 6, 18 and 36 h post-injection, respectively, which were significantly higher than that of moderate EGFR expressing tumors (A549), with SUVs of 0.89±0.16, 4.70±0.81, 2.01±0.50 at 6, 18 and 36 h post-injection, respectively. The expression levels of A431 and A549 were confirmed by western blotting. Additionally, the tracer uptake in A431 tumors can be blocked by unlabeled cetuximab, suggesting that tracer uptake by tumors was receptor-mediated. Furthermore, NIRF imaging using Cy5.5-C225 showed that the fluorescence intensity in tumors increased with time, with a maximal intensity of 8.17E+10 (p/s/cm²/sr)/(μW/cm²) at 48 h post-injection, which is consistent with the paradigm from micro-PET imaging in A431 tumor-bearing mice.

Conclusions

The ⁶⁴Cu-NOTA-C225 PET imaging may be able to specifically and sensitively differentiate tumor models with different EGFR expression levels. It offers potentials as a PET radiotracer for imaging of tracer EGFR-positive tumors.

Predictive Value of Cetuximab-Induced Skin Toxicity in Recurrent or Metastatic Squamous Cell Carcinoma of the Head and NECK

Background: Skin toxicity is a common adverse event during cetuximab (Cmab) treatment. However, few reports have investigated the correlation between skin toxicity and the efficacy of Cmab in patients with recurrent or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN).

Methods: We retrospectively reviewed 112 R/M SCCHN patients who received palliative chemotherapy with Cmab. Main eligibility criteria included primary disease in the oral cavity, hypopharynx, nasopharynx, oropharynx, or larynx; no prior history of EGFR-directed therapy; receipt of Cmab plus chemotherapy as first-line therapy for recurrent or metastatic disease; and follow-up for more than 90 days. We analyzed the time to first occurrence and time of maximum grade skin toxicity, and its predictive value with regard to treatment efficacy.

Results: After a median follow-up of 393 days (range 109–1501 days), 105 (94%) and 20 (18%) patients had skin toxicity of any grade and grade 3, respectively. Among them, 8 patients with grade 3 acneiform rash, skin rash, or paronychia within 90 days after treatment initiation (“early skin toxicity”) had improved progression-free survival (PFS) (log-rank test, P = 0.045; 2-year PFS, 25.0 vs. 2.9%) and overall survival (OS) (log-rank test, P = 0.023, 2-year OS, 50.0 vs. 14.4%) compared with those with < grade 3 toxicity. A greater proportion of patients with early skin toxicity than patients without this toxicity could proceed with Cmab maintenance (88 vs. 44%, P = 0.021). Multivariate analysis identified early skin toxicity as an independent predictor of better PFS (hazard ratio [HR] = 0.363, 95% confidence interval [CI] 0.142–0.924, P = 0.034) and OS (HR = 0.187, 95% CI: 0.045–0.781, P = 0.022).

Conclusion: Grade 3 Cmab-induced skin toxicity within 90 days was associated with better survival in R/M SCCHN. Effective rash management therefore seems necessary to realize the benefit of Cmab treatment.

Successful desensitization of a patient with cetuximab hypersensitivity: A case report

BACKGROUND

Severe hypersensitivity reaction is a dangerous adverse drug reaction in patients receiving cetuximab. It requires drug discontinuation and medical management.

CASE DESCRIPTION

A 48-year-old man, previously diagnosed with metastatic colorectal cancer, was admitted for therapy continuation. During the first infusion of cetuximab, the patient experienced acute signs of hypersensitivity reactions. The treatment team decided to administer cetuximab employing the desensitization protocol.

CONCLUSIONS

This study reports a severe hypersensitivity reaction to cetuximab in an adult patient with colorectal cancer. This patient was successfully managed with a new safe and rapid desensitization protocol.

A Multi-Arm Phase I Study of the PI3K/mTOR Inhibitors PF-04691502 and Gedatolisib (PF-05212384) plus Irinotecan or the MEK Inhibitor PD-0325901 in Advanced Cancer

Background

This phase I, four-arm, open-label study (NCT01347866) evaluated the PI3K/mTOR inhibitors PF-04691502 (arms A, B) and gedatolisib (PF-05212384; arms C, D) in combination with the MEK inhibitor PD-0325901 (arm A, D) or irinotecan (arm B, C) in patients with advanced solid tumors.

Objectives

Primary endpoint was dose-limiting toxicity with each combination. Secondary endpoints included safety, pharmacokinetics and preliminary antitumor activity.

Patients and Methods

Dose escalation followed a 3 + 3 design in arm C and a zone-based design in arm D.

Results

The PF-04691502 combination arms were closed prematurely due to low tolerability, and the maximum tolerated doses (MTDs) were not determined for either arm. The MTD for the combination of gedatolisib with irinotecan 180 mg/m² was estimated to be 110 mg weekly and for the combination with PD-0325901 was not reached at the highest dose evaluated (gedatolisib 154 mg weekly). Plasma concentrations of gedatolisib were generally similar across dose groups in arm C (with irinotecan) and arm D (with PD-0325901). Frequent dose delays or dose reductions were required for both combinations, potentially preventing sustained therapeutic drug concentrations. Gedatolisib plus irinotecan produced a response rate of ~5% and clinical benefit in 16% of patients with advanced colorectal cancer (progression-free survival, 2.8 months). Preliminary evidence of clinical activity was observed with gedatolisib plus PD-0325901 in patients with ovarian cancer (three partial responses, n = 5) or endometrial cancer (one partial response, n = 1) and KRAS mutations.

Conclusions

Further evaluations of gedatolisib are warranted in patients with advanced solid malignancies.

Electronic supplementary material

The online version of this article (10.1007/s11523-017-0530-5) contains supplementary material, which is available to authorized users.

Panitumumab in the treatment of metastatic colorectal cancer, including wild-type RAS, KRAS and NRAS mCRC

The humanized monoclonal antibody panitumumab, targeted against EGFR, plays an important role in patients with metastatic colorectal cancer. This article reviews the body of evidence for panitumumab which demonstrates significant benefits across multiple lines of therapy in those without an extended RAS mutation. The use of panitumumab with RAS mutations is not beneficial and possibly harmful. Panitumumab is well tolerated with manageable toxicities. The role of panitumumab continues to evolve as understanding of sequencing of therapies grows. There is evidence for use as maintenance therapy and conversion therapy for unresectable liver metastases. Future research is likely to focus on biomarkers for improved patient selection and the development of novel therapeutic strategies to overcome resistance.

Development and Clinical Indications of Cetuximab

Cetuximab is a chimeric immunoglobulin G1 monoclonal antibody that targets the extracellular domain of the epidermal growth factor receptor (EGFR) with high specificity and affinity. It competitively inhibits endogenous ligand binding and thereby inhibits subsequent EGFR activation. The EGFR signaling pathways regulate cell differentiation, proliferation, migration, angiogenesis and apoptosis, all of which become deregulated in cancer cells. EGFR is an important target for cancer therapy and many studies have demonstrated that cetuximab is active in several types of cancer, particularly colorectal and head and neck cancer. Cetuximab enhances the effects of many standard cytotoxic agents, including irinotecan, and in combination with chemotherapy it can elicit antitumor responses in tumors that previously failed to respond to that chemotherapy. Cetuximab also enhances radiation-induced apoptosis. On the basis of a pivotal European randomized study (the BOND study) and of 2 clinical studies conducted in the USA, cetuximab has been approved in combination with irinotecan for patients affected by EGFR-expressing metastatic colon cancer after failure with irinotecan. There have only been a few small phase II trials on first-line treatment in metastatic colorectal cancer, but the results suggest promising activity of cetuximab together with irinotecan or oxaliplatin. There is some evidence that additive efficacy can be achieved using EGFR inhibitors in combination with vascular endothelial growth factor receptor inhibitors such as bevacizumab. A correlation between response and the main toxicity (acne-like skin reaction) has been observed but is unclear. EGFR status as a specific marker for EGFR inhibitors is controversial. At the moment, EGFR expression does not appear to be a predictive factor for response to EGFR inhibitors.

The Future of Anti-EGFR Therapy

We report here on the state of our knowledge of the target - namely, the epidermal growth factor (EGF) and its receptor - and the challenges related to the methods of determination of the epidermal growth factor receptor (EGFR) and associated molecular pathways. A critical review of the anti-EGFR therapeutic strategies is also outlined. The chimeric anti-EGFR monoclonal antibody cetuximab has been approved for EGFR-expressing colorectal tumors in patients who progress after irinotecan-based chemotherapy in combination with irinotecan and in squamous cell head and neck carcinomas for patients with locally advanced disease in combination with radiation therapy or after failure of platinum-based chemotherapy in recurrent or metastatic disease (FDA). Cetuximab has the potential to provide an improvement of clinical outcome also in other indications and tumor types, particularly when used as first-line therapy combined with standard chemotherapy for metastatic disease or in the adjuvant setting. Possible strategies to improve the effectiveness of anti-EGFR agents are suggested and include (i) the use of predictive tools capable of making a more rational selection of patients; (ii) the development of standardized predictive biomarkers as surrogates for early monitoring of drug efficacy; and (iii) adequate study design, statistical analysis and proper end points of efficacy to be applied in future prospective trials.

Cetuximab response in CRC patient-derived xenografts seems predicted by an expression based RAS pathway signature

Cetuximab is an approved treatment for metastatic colorectal carcinoma (mCRC) with codon 12/13-KRAS mutations, recently questioned for its validity, and alternative mutation-based biomarkers were proposed. We set out to investigate whether an expression signature can also predict response by utilizing a cetuximab mouse clinical trial (MCT) dataset on a cohort of 25 randomly selected EGFR⁺ CRC patient-derived xenografts (PDXs). While we found that the expression of EGFR and its ligands are not predictive of the cetuximab response, we tested a published RAS pathway signature, a 147-gene expression signature proposed to describe RAS pathway activity, against this MCT dataset. Interestingly, our study showed that the observed cetuximab activity has a strong correlation with the RAS pathway signature score, which was also demonstrated to have a certain degree of correlation with a historic clinical dataset. Altogether, the independent validations in unrelated datasets from independent cohort of CRCs strongly suggest that RAS pathway signature may be a relevant expression signature predictive of CRC response to cetuximab. Our data seem to suggest that an mRNA expressing signature may also be developed as a predictive biomarker for drug response, similarly to genetic mutations.

Carcinoembryonic Antigen in Monitoring of Response to Cetuximab plus FOLFIRI or FOLFOX-4 in Patients with Metastatic Colorectal Cancer

First-line treatment of metastatic colorectal cancer with combinations of cetuximab and irinotecan-based or oxaliplatin-based chemotherapy has shown promising efficacy. The clinical response to such treatment is generally assessed by tumor measurement through imaging. This study was performed to evaluate the correlation between serial changes in imaging results and carcinoembryonic antigen (CEA) levels. In 64 patients with metastatic colorectal cancer receiving cetuximab plus FOLFIRI or FOLFOX-4 chemotherapy we retrospectively analyzed the relationship between changes in serum CEA and changes in imaging results throughout the treatment course. Response in terms of serum CEA change was defined as a ≥50% drop in CEA level for more than 4 weeks. The sensitivity and specificity of serum CEA changes after targeted chemotherapy in relation to imaging results were 80.5% (33/41) and 73.9% (17/23), respectively, with a diagnostic accuracy of 78.1% (50/64). The progression-free survival time of responders assessed by serum CEA change was significantly longer than that of nonresponders (p=0.0091). Our results highlight the importance of serum CEA monitoring in assessing the response to targeted chemotherapy and in predicting the prognosis of patients with metastatic colorectal cancer.

Cost-Effectiveness of Cetuximab as First-line Treatment for Metastatic Colorectal Cancer in the United States

PURPOSE

We conducted a cost-effectiveness analysis incorporating recent phase III clinical trial (FIRE-3) data to evaluate clinical and economic tradeoffs associated with first-line treatments of KRAS wild-type (WT) metastatic colorectal cancer (mCRC).

MATERIALS AND METHODS

A cost-effectiveness model was developed using FIRE-3 data to project survival and lifetime costs of FOLFIRI plus either cetuximab or bevacizumab. Hypothetical KRAS-WT mCRC patients initiated first-line treatment and could experience adverse events, disease progression warranting second-line treatment, or clinical response and hepatic metastasectomy. Model inputs were derived from FIRE-3 and published literature. Incremental cost-effectiveness ratios (ICERs) were reported as US$ per life year (LY) and quality-adjusted life year (QALY). Scenario analyses considered patients with extended RAS mutations and CALGB/SWOG 80405 data; 1-way and probabilistic sensitivity analyses were conducted.

RESULTS

Compared with bevacizumab, KRAS-WT patients receiving first-line cetuximab gained 5.7 months of life at a cost of $46,266, for an ICER of $97,223/LY ($122,610/QALY). For extended RAS-WT patients, the ICER was $77,339/LY ($99,584/QALY). Cetuximab treatment was cost-effective 80.3% of the time, given a willingness-to-pay threshold of $150,000/LY. Results were sensitive to changes in survival, treatment duration, and product costs.

CONCLUSIONS

Our analysis of FIRE-3 data suggests that first-line treatment with cetuximab and FOLFIRI in KRAS (and extended RAS) WT mCRC patients may improve health outcomes and use financial resources more efficiently than bevacizumab and FOLFIRI. This information, in combination with other studies investigating comparative effectiveness of first-line options, can be useful to clinicians, payers, and policymakers in making treatment and resource allocation decisions for mCRC patients.

Therapeutic Antibodies in Cancer Therapy

The therapeutic arsenal in solid tumors comprises different anticancer strategies with diverse chemotherapeutic agents and a growing number of biological substances. Large clinical study-based chemotherapeutic protocols combined with biologicals have become an important component in (neo-) adjuvant therapy alongside surgery in solid cancers as well as radiation therapy in some instances. In recent years, monoclonal antibodies have entered the mainstream of cancer therapy. Their first use was as antagonists of oncogenic receptor tyrosine kinases, but today monoclonal antibodies have emerged as long-sought vehicles for the targeted delivery of potent chemotherapeutic agents and as powerful tools to manipulate anticancer immune responses. There is a growing number of FDA approved monoclonal antibodies and small molecules targeting specific types of cancer suggestive of the clinical relevance of this approach.Targeted cancer therapies , also referred to as personalized medicine, are being studied for use alone, in combination with other targeted therapies, and in combination with chemotherapy. The use of monoclonal antibodies in colorectal and gastric cancer for example have shown best outcome when combined with chemotherapy, even though single agent anti-EGFR antibodies seem to be active in particular setting of metastatic colorectal cancer patients. However, it is not well defined whether the addition of anti-VEGF - and anti-EGFR strategies to chemotherapy could improve outcome in those patients susceptible to colorectal cancer-related metastases resection. Among the most promising approaches to activating therapeutic antitumor immunity is the blockade of immune checkpoints, exemplified by the recently FDA-approved agent, Ipilimumab, an antibody that blocks the coinhibitory receptor CTLA-4. Capitalizing on the success of Ipilimumab, agents that target a second coinhibitory receptor, PD-1, or its ligand, PD-L1, are in clinical development. This section attempts to discuss recent progress of targeted agents and in tackling a more general target applicable to gastrointestinal cancer .

Challenges and future of biomarker tests in the era of precision oncology: Can we rely on immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH) to select the optimal patients for matched therapy?

Molecular techniques have improved our understanding of the pathogenesis of cancer development. These techniques have also fueled the rational development of targeted drugs for patient populations stratified by their genetic characteristics. These novel methods have changed the classic paradigm of diagnostic pathology; among them are IHC, FISH, polymerase chain reaction (PCR) and microarray technology. IHC and FISH detection methods for human epidermal growth factor receptor-2 (HER2), epidermal growth factor receptor (EGFR) and programmed death ligand-1 (PD-L1) were recently approved by the Food and Drug Administration (FDA) as routine clinical practice for cancer patients. Here, we discuss general challenges related to the predictive power of these molecular biomarkers for targeted therapy in cancer medicine. We will also discuss the prospects of utilizing new biomarkers for fibroblast growth factor receptor (FGFR) and hepatocyte growth factor receptor (cMET/MET) targeted therapies for developing new and robust predictive biomarkers in oncology.

Phase Ib Study of Lumretuzumab Plus Cetuximab or Erlotinib in Solid Tumor Patients and Evaluation of HER3 and Heregulin as Potential Biomarkers of Clinical Activity

Purpose: This study investigated the safety, clinical activity, and target-associated biomarkers of lumretuzumab, a humanized, glycoengineered, anti-HER3 monoclonal antibody (mAb), in combination with the EGFR-blocking agents erlotinib or cetuximab in patients with advanced HER3-positive carcinomas.Experimental Design: The study included two parts: dose escalation and dose extension phases with lumretuzumab in combination with either cetuximab or erlotinib, respectively. In both parts, patients received lumretuzumab doses from 400 to 2,000 mg plus cetuximab or erlotinib according to standard posology, respectively. The effect of HRG mRNA and HER3 mRNA and protein expression were investigated in a dedicated extension cohort of squamous non-small cell lung cancer (sqNSCLC) patients treated with lumretuzumab and erlotinib.Results: Altogether, 120 patients were treated. One dose-limiting toxicity (DLT) in the cetuximab part and two DLTs in the erlotinib part were reported. The most frequent adverse events were gastrointestinal and skin toxicities, which were manageable. The objective response rate (ORR) was 6.1% in the cetuximab part and 4.2% in the erlotinib part. In the sqNSCLC extension cohort of the erlotinib part, higher tumor HRG and HER3 mRNA levels were associated with a numerically higher disease control rate but not ORR.Conclusions: The toxicity profile of lumretuzumab in combination with cetuximab and erlotinib was manageable, but only modest clinical activity was observed across tumor types. In the sqNSCLC cohort, there was no evidence of meaningful clinical benefit despite enriching for tumors with higher HRG mRNA expression levels. Clin Cancer Res; 23(18); 5406-15. ©2017 AACR.

Harnessing Integrative Omics to Facilitate Molecular Imaging of the Human Epidermal Growth Factor Receptor Family for Precision Medicine

Cancer is a growing problem worldwide. The cause of death in cancer patients is often due to treatment-resistant metastatic disease. Many molecularly targeted anticancer drugs have been developed against 'oncogenic driver' pathways. However, these treatments are usually only effective in properly selected patients. Resistance to molecularly targeted drugs through selective pressure on acquired mutations or molecular rewiring can hinder their effectiveness. This review summarizes how molecular imaging techniques can potentially facilitate the optimal implementation of targeted agents. Using the human epidermal growth factor receptor (HER) family as a model in (pre)clinical studies, we illustrate how molecular imaging may be employed to characterize whole body target expression as well as monitor drug effectiveness and the emergence of tumor resistance. We further discuss how an integrative omics discovery platform could guide the selection of 'effect sensors' - new molecular imaging targets - which are dynamic markers that indicate treatment effectiveness or resistance.

Single nucleotide polymorphisms in the IGF-IRS pathway are associated with outcome in mCRC patients enrolled in the FIRE-3 trial

The Insulin-like growth factor (IGF)/IGF-receptor pathway with its scaffolding proteins Insulin Receptor Substrate (IRS)1 and IRS2 are crucial regulators of metabolism and progression in metastatic colorectal cancer (mCRC). The goal of the study was the identification of predictive and prognostic markers among IRS1, IRS2, IGF1 and IGF-1R SNPs in mCRC patients enrolled in the FIRE-3 trial. Four SNPs of IRS (IRS1 rs1801278, rs1801123; IRS2 rs1805097, rs2289046) and four SNPs of IGF1-IGFR1 (rs6214, rs6220, rs2946834, rs2016347) were analyzed by PCR/direct-sequencing in the FIRE-3 trial. The relation of SNPs with PFS and OS was evaluated through Kaplan-Meier method and log-rank test in the overall population and in subgroup according to RAS status and treatment arm. In the overall population IRS1 rs1801123 C/- carriers (N= 105) achieved significantly worse OS compared to T/T (N = 464) in univariate (HR = 1.32 [95%CI 1.03-1.70], p = 0.029) and in multivariable. Similar results were observed among RAS wild type. Patients with IGF1 rs2946834 T/- variant (N= 280) achieved improved PFS compared to C/C (N = 257) in univariate (HR = 0.77 [95%CI 0.64-0.92], p = 0.004) and in multivariable. In the RAS wild-type subgroup IGF1 rs2946834 T/- carriers showed better PFS and OS compared to C/C (univariate HR for PFS = 0.65 [95%CI 0.51-0.81], p < 0.001; multivariable HR for PFS = 0.63 [95%CI 0.50-0.81], p < 0.001). IRS1 rs1801123 SNP was identified as a new prognostic marker for mCRC. IGF1 rs2946834 was confirmed as prognostic factor in the overall population and in RAS wild type patients. Our findings underline the importance of IGF downstream signaling pathway in RAS wild-type mCRC patient.

The cardiotoxicity of cetuximab as single therapy in Chinese chemotherapy-refractory metastatic colorectal cancer patients

The cardiac safety of cetuximab, particularly as single approach, has not been investigated extensively. This trial was designed to evaluate the cardiac safety of cetuximab as salvage monotherapy in Chinese chemotherapy-refractory metastatic colorectal cancer (mCRC) patients.Cetuximab was administrated at an initial dose of 400 mg/mon day 1 (week 1), followed by a maintenance dose of 250 mg/m on day 1 of each 7-day cycle. Electrocardiograph (ECG), routine laboratory tests, and troponin I (TNI) Ultra were performed at baseline, during, and after the cetuximab therapy. The incidence of abnormal ECGs, elevated TNI Ultra, cardiac events, and noncardiac events were recorded and analyzed.TNI Ultra+ was found in 20 patients (32.3%) during the cetuximab therapy.TNI Ultra+ occurred more frequently in patients with more than 3 organs affected and accepted fourth or above lines of chemotherapy. The most frequent abnormal ECG was ST depression in 24 (38.7%) patients. The elevated TNI Ultra and abnormal ECGs could recover after the cetuximab therapy. The most of cardiac adverse events were mild and transient and the noncardiac adverse events were also consistent with the known safety profile for cetuximab.Cetuximab showed its cardiac safety as a single agent for chemotherapy-refractory mCRC patients. And TNI Ultra and ECG could be sensitive and convenient approaches for the surveillance of adverse events.

EGFR Gene Amplification and KRAS Mutation Predict Response to Combination Targeted Therapy in Metastatic Colorectal Cancer

Genetic variability in KRAS and EGFR predicts response to cetuximab in irinotecan refractory colorectal cancer. Whether these markers or others remain predictive in combination biologic therapies including bevacizumab is unknown. We identified predictive biomarkers from patients with irinotecan refractory metastatic colorectal cancer treated with cetuximab plus bevacizumab. Patients who received cetuximab plus bevacizumab for irinotecan refractory colorectal cancer in either of two Phase II trials conducted were identified. Tumor tissue was available for 33 patients. Genomic DNA was extracted and used for mutational analysis of KRAS, BRAF, and p53 genes. Fluorescence in situ hybridization was performed to assess EGFR copy number. The status of single genes and various combinations were tested for association with response. Seven of 33 patients responded to treatment. KRAS mutations were found in 14/33 cases, and 0 responded to treatment (p = 0.01). EGFR gene amplification was seen in 3/33 of tumors and in every case was associated with response to treatment (p < 0.001). TP53 and BRAF mutations were found in 18/33 and 0/33 tumors, respectively, and there were no associations with response to either gene. EGFR gene amplification and KRAS mutations are predictive markers for patients receiving combination biologic therapy of cetuximab plus bevacizumab for metastatic colorectal cancer. One marker or the other is present in the tumor of half of all patients allowing treatment response to be predicted with a high degree of certainty. The role for molecular markers in combination biologic therapy seems promising.

On-treatment markers as predictors to guide anti-EGFR MoAb treatment in metastatic colorectal cancer: a systematic review with meta-analysis

PURPOSE

Skin toxicity (ST) and early tumor shrinkage (ETS) are early phenomenon during the anti-epidermal growth factor receptor (EGFR) monoclonal antibody (MoAb) treatment. We conducted a meta-analysis and included relevant studies that reported the impact of ST and ETS on survival- and life quality-based outcome of metastatic colorectal cancer (mCRC) patients treated with anti-EGFR MoAb.

METHODS

Relevant studies were identified from PubMed and Embase reporting the correlation of ST and ETS with the clinical outcome of mCRC patients treated with anti-EGFR MoAb. We also collected evidences on the impact of ST and ETS on absolute benefit acquired from additional anti-EGFR treatment and quality of life (ST only). Pooled hazard ratio and rate difference were all estimated by using random-effects model.

RESULTS

Pooled data revealed that the occurrence of ST and ETS ≥20% (v < 20%) during anti-EGFR MoAb treatment were both associated with better OS, PFS and ORR. This association could not be disturbed by KRAS status. Mean changes in safety follow-up life health state from baseline appeared unaffected by ST. Only mCRC patients with wild-type KRAS tumor who suffered grade 2+ ST could benefit from additional anti-EGFR treatment to chemotherapy or best supportive care (BSC) alone. ETS was also a predictor for absolute survival benefit acquired from additional anti-EGFR treatment for patients with wild-type KRAS tumors, and the more early shrinkage the tumor was, the much benefit was observed.

CONCLUSION

ST and ETS are predictive of absolute benefit acquired from anti-EGFR treatment in mCRC patients with wild-type KRAS tumors. These two on-treatment markers can be used for clinical decision-making if no adequate biological markers from tissues are provided.

Blood-based markers of efficacy and resistance to cetuximab treatment in metastatic colorectal cancer: results from CALGB 80203 (Alliance)

Circulating protein markers were assessed in patients with colorectal cancer (CRC) treated with cetuximab in CALGB 80203 to identify prognostic and predictive biomarkers. Patients with locally advanced or metastatic CRC received FOLFOX or FOLFIRI chemotherapy (chemo) or chemo in combination with cetuximab. Baseline plasma samples from 152 patients were analyzed for six candidate markers [epidermal growth factor (EGF), heparin‐binding EGF (HBEGF), epidermal growth factor receptor (EGFR), HER2, HER3, and CD73]. Analyte levels were associated with survival endpoints using univariate Cox proportional hazards models. Predictive markers were identified using a treatment‐by‐marker interaction term in the Cox model. Plasma levels of EGF, HBEGF, HER3, and CD73 were prognostic for overall survival (OS) across all patients (KRAS mutant and wild‐type). High levels of EGF predicted for lack of OS benefit from cetuximab in KRAS wild‐type (WT) patients (chemo HR = 0.98, 95% CI = 0.74–1.29; chemo+cetuximab HR = 1.54, 95% CI = 1.05–2.25; interaction P = 0.045) and benefit from cetuximab in KRAS mutant patients (chemo HR = 1.72, 95% CI = 1.02–2.92; chemo+cetuximab HR = 0.90, 95% CI = 0.67–1.21; interaction P = 0.026). Across all patients, higher HER3 levels were associated with significant OS benefit from cetuximab treatment (chemo HR = 4.82, 95% CI = 1.68–13.84; chemo+cetuximab HR = 0.95, 95% CI = 0.31–2.95; interaction P = 0.046). CD73 was also identified as predictive of OS benefit in KRASWT patients (chemo HR = 1.28, 95% CI = 0.88–1.84; chemo+cetuximab HR = 0.60, 95% CI = 0.32–1.13; interaction P = 0.049). Although these results are preliminary, and confirmatory studies are necessary before clinical application, the data suggest that HER3 and CD73 may play important roles in the biological response to cetuximab.

New findings on primary and acquired resistance to anti-EGFR therapy in metastatic colorectal cancer: do all roads lead to RAS?

Anti-epidermal growth factor receptor therapy with the monoclonal antibodies cetuximab and panitumumab is the main targeted treatment to combine with standard chemotherapy for metastatic colorectal cancer. Many clinical studies have shown the benefit of the addition of these agents for patients without mutations in the EGFR pathway. Many biomarkers, including KRAS and NRAS mutations, BRAF mutations, PIK3CA mutations, PTEN loss, AREG and EREG expression, and HER-2 amplification have already been identified to select responders to anti-EGFR agents. Among these alterations KRAS and NRAS mutations are currently recognized as the best predictive factors for primary resistance. Liquid biopsy, which helps to isolate circulating tumor DNA, is an innovative method to study both primary and acquired resistance to anti-EGFR monoclonal antibodies. However, high-sensitivity techniques should be used to enable the identification of a wide set of gene mutations related to resistance.

High-throughput RNAi screening of human kinases identifies predictors of clinical outcome in colorectal cancer patients treated with oxaliplatin

The purpose of this study is to identify protein kinase genes that modulate oxaliplatin cytotoxicity in vitro and evaluate the roles of these genes in predicting clinical outcomes in CRC patients receiving oxaliplatin-based adjuvant chemotherapy. A high-throughput RNAi screening targeting 626 human kinase genes was performed to identify kinase genes whose inhibition potentiates oxaliplatin sensitivity in CRC cells. The associations between copy numbers of the candidate genes and recurrence-free survival and overall survival were analyzed in 142 stage III CRC patients receiving first-line oxaliplatin-based adjuvant chemotherapy who were enrolled from two independent hospitals. HT-RNAi screening identified 40 kinase genes whose inhibition potentiated oxaliplatin cytotoxicity in DLD1 cells. The relative copy number (RCN) of MAP4K1 and CDKL4 were associated with increased risks of both recurrence and death. Moreover, significant genes-based risk score and the ratios of RCN of different genes can further categorize patients into subgroups with distinctly differing outcomes. The estimated AUC for the prediction models including clinical variables plus kinase biomarkers was 0.77 for the recurrence and 0.82 for the survival models. The copy numbers of MAP4K1 and CDKL4 can predict clinical outcomes in CRC patients treated with oxaliplatin-based chemotherapy.

Correlation Between the Severity of Cetuximab-Induced Skin Rash and Clinical Outcome for Head and Neck Cancer Patients: The RTOG Experience

PURPOSE

To evaluate the severity of cetuximab-induced skin rash and its correlation with clinical outcome and late skin toxicity in patients with head and neck squamous cell carcinoma treated with chemoradiation therapy and cetuximab.

METHODS AND MATERIALS

Analysis included patients who received loading dose and ≥1 cetuximab dose concurrent with definitive chemoradiation therapy (70 Gy + cisplatin) or postoperative chemoradiation therapy (60-66 Gy + docetaxel or cisplatin).

RESULTS

Six hundred two patients were analyzed; 383 (63.6%) developed grade 2 to 4 cetuximab rash. Patients manifesting grade 2 to 4 rash had younger age (P<.001), fewer pack-years smoking history (P<.001), were more likely to be males (P=.04), and had p16-negative (P=.04) oropharyngeal tumors (P=.003). In univariate analysis, grade 2 to 4 rash was associated with better overall survival (hazard ratio [HR] 0.58, P<.001) and progression-free survival (HR 0.75, P=.02), and reduced distant metastasis rate (HR 0.61, P=.03), but not local-regional failure (HR 0.79, P=.16) relative to grade 0 to 1 rash. In multivariable analysis, HRs for overall survival, progression-free survival, distant metastasis, and local-regional failure were, respectively, 0.68 (P=.008), 0.85 (P=.21), 0.64 (P=.06), and 0.89 (P=.48). Grade ≥2 rash was associated with improved survival in p16-negative patients (HR 0.28 [95% confidence interval 0.11-0.74]) but not in p16-positive patients (HR 1.10 [0.42-2.89]) (P=.05 for interaction). Twenty-five percent of patients with grade 2 to 4 acute in-field radiation dermatitis experienced grade 2 to 4 late skin fibrosis, versus 14% of patients with grade 0 to 1 acute in-field radiation dermatitis (P=.002).

CONCLUSION

Grade 2 to 4 cetuximab rash was associated with better survival, possibly due to reduction of distant metastasis. This observation was noted mainly in p16-negative patients. Grade 2 to 4 acute in-field radiation dermatitis was associated with higher rate of late grade 2 to 4 skin fibrosis.

Second-line panitumumab as a triweekly dose for patients with wild-type KRAS exon 2 metastatic colorectal cancer: a single-institution experience

OBJECTIVE

Panitumumab administered as monotherapy in colorectal cancer (CRC) has shown response and disease stabilization rates of approximately 30%. The current study aimed to evaluate the progression-free survival (PFS) and overall survival (OS) of patients with metastatic colorectal cancer (mCRC) treated with panitumumab every 3 weeks as a second line treatment.

METHODS

This study is a retrospective analysis of 18 patients, aged more than 18 years, with wild-type KRAS exon 2 mCRC treated with panitumumab as a second-line single agent after progression on first-line chemotherapy.

RESULTS

The median number of courses received was 10 (range, 4-29), and the median duration of treatment was 30 weeks (range, 12-96 weeks). After a median follow-up period of 13 months, the median PFS was 6 months (range, 4.3-7.7 months) and the median OS was 11 months (range, 7.4-14.5 months). The median PFS was 4 months for patients with < grade 2 skin toxicity and 6 months (range, 4.5-7.5 months) for patients with ≥grade 2 skin rash (P=0.05). The median OS was 9 months (range, 6.4-11.5 months) and 14 months (range, 11.6-16.3 months) for the two groups of patients (P=0.002).

CONCLUSIONS

Panitumumab given every 3 weeks is effective and well tolerated in patients with advanced CRC that progressed after standard chemotherapy.

Premedication and Chemotherapy Agents do not Impair Imgatuzumab (GA201)-Mediated Antibody-Dependent Cellular Cytotoxicity and Combination Therapies Enhance Efficacy

PURPOSE

Imgatuzumab (GA201) is a novel anti-EGFR mAb that is glycoengineered for enhanced antibody-dependent cellular cytotoxicity (ADCC). Future treatment schedules for imgatuzumab will likely involve the use of potentially immunosuppressive drugs, such as premedication therapies, to mitigate infusion reactions characteristic of mAb therapy and chemotherapy combination partners. Because of the strong immunologic component of mode of action of imgatuzumab, it is important to understand whether these drugs influence imgatuzumab-mediated ADCC and impact efficacy.

EXPERIMENTAL DESIGN

We performed a series of ADCC assays using human peripheral blood mononuclear cells that were first preincubated in physiologically relevant concentrations of commonly used premedication drugs and cancer chemotherapies. The ability of common chemotherapy agents to enhance the efficacy of imgatuzumab in vivo was then examined using orthotopic xenograft models of human cancer.

RESULTS

A majority of premedication and chemotherapy drugs investigated had no significant effect on the ADCC activity of imgatuzumab in vitro Furthermore, enhanced in vivo efficacy was seen with imgatuzumab combination regimens compared with single-agent imgatuzumab, single-agent chemotherapy, or cetuximab combinations.

CONCLUSIONS

These data indicate that medications currently coadministered with anti-EGFR therapies are unlikely to diminish the ADCC capabilities of imgatuzumab. Further studies using syngeneic models with functional adaptive T-cell responses are now required to fully understand how chemotherapy agents will influence a long-term response to imgatuzumab therapy. Thus, this study and future ones can provide a framework for designing imgatuzumab combination regimens with enhanced efficacy for investigation in phase II trials. Clin Cancer Res; 22(10); 2453-61. ©2015 AACR.

Cetuximab Reconstitutes Pro-Inflammatory Cytokine Secretions and Tumor-Infiltrating Capabilities of sMICA-Inhibited NK Cells in HNSCC Tumor Spheroids

Immunosuppressive factors, such as soluble major histocompatibility complex class I chain-related peptide A (sMICA) and transforming growth factor beta 1 (TGF-β₁), are involved in tumor immune escape mechanisms (TIEMs) exhibited by head and neck squamous cell carcinomas (HNSCCs) and may represent opportunities for therapeutic intervention. In order to overcome TIEMs, we investigated the antibody-dependent cellular cytotoxicity (ADCC), cytokine release and retargeted tumor infiltration of sMICA-inhibited patient NK cells expressing Fcγ receptor IIIa (FcγRIIIa, CD16a) in the presence of cetuximab, an anti-epidermal growth factor receptor (HER1) monoclonal antibody (mAb). Compared to healthy controls, relapsed HNSCC patients (n = 5), not currently in treatment revealed decreased levels of circulating regulatory NK cell subsets in relation to increased cytotoxic NK cell subpopulations. Elevated sMICA and TGF-β₁ plasma levels correlated with diminished TNFα and IFN-γ release and decreased NKG2D (natural killer group 2 member D)-dependent killing of HNSCC cells by NK cells. Incubation of IL-2-activated patient NK cells with patient plasma containing elevated sMICA or sMICA analogs (shed MICA and recombinant MICA) significantly impaired NKG2D-mediated killing by down-regulation of NKG2D surface expression. Of note, CD16 surface expression levels, pro-apoptotic and activation markers, and viability of patient and healthy donor NK cell subpopulations were not affected by this treatment. Accordingly, cetuximab restored killing activity of sMICA-inhibited patient NK cells against cetuximab-coated primary HNSCC cells via ADCC in a dose-dependent manner. Rapid reconstitution of anti-tumor recognition and enhanced tumor infiltration of treated NK cells was monitored by 24 h co-incubation of HNSCC tumor spheroids with cetuximab (1 μg/ml) and was characterized by increased IFN-γ and TNFα secretion. This data show that the impaired NK cell-dependent tumor surveillance in relapsed HNSCC patients could be reversed by the re-establishment of ADCC-mediated effector cell activity, thus supporting NK cell-based immunotherapy in combination with antineoplastic monoclonal mAbs.

Precision medicine in colorectal cancer: evolving genomic landscape and emerging consensus

Colorectal cancer is the third most lethal cancer in men and women in the USA. Although surgical resection is the mainstay of treatment, many patients develop local and widely metastatic disease and become resistant to conventional chemotherapeutics. Recent comprehensive molecular characterization has led to subclassification of colorectal adenocarcinoma based on molecular properties, such as microsatellite instability and high CpG island methylation. These emerging subclassifications are associate with varying frequencies of RAS, BRAF, APC and other genetic events and have the ability to redefine therapeutic regimens. In this review, we examine how molecular diagnostics are currently used while providing insight into emerging implications for molecular analysis for personalized therapy in colorectal cancer.

Personalized Approaches to Gastrointestinal Cancers: Importance of Integrating Genomic Information to Guide Therapy

Cancers are characterized by complex tumor heterogeneity driven by subclones with differential genotypes and phenotypes, which then drives cancer behavior. As genomic strategies become feasible on smaller samples such as biopsies, coupled with decreasing costs of these approaches, clinicians will increasingly use genomic information to drive therapeutic decision making. Early applications of such personalized approaches are discussed. Genetic testing of high-risk family members may identify patients with germline mutations who can have prophylactic surgeries as a cancer prevention strategy. This article discusses examples of successful targeted therapy. Clinical trials need to incorporate genetic testing to stratify patients into different groups.

The Notch pathway in colorectal cancer

Colorectal cancer (CRC) is the third leading cause of cancer death worldwide. It is also the third most common cancer diagnosis among men, and the second most common cancer diagnosis among women. Globally, CRC can account for nearly 694,000 annual deaths. It is widely appreciated that CRC is the result of dysregulated cellular pathways that promote an inappropriate stem-cell-like phenotype, apoptotic resistance, unchecked proliferation and metastatic spread. While no single pathway is responsible for all of these attributes, an array of recent studies suggests a pivotal role for abnormal Notch-1 signaling in CRC, in part due to interconnectivity of Notch with other pathways. This review will summarize recent evidence for a role of Notch signaling in CRC, will consider interconnectivity between Notch and other pathways involved in CRC and will discuss the possible utility of targeting Notch as a CRC therapeutic.

A let-7 microRNA-binding site polymorphism in KRAS predicts improved outcome in patients with metastatic colorectal cancer treated with salvage cetuximab/panitumumab monotherapy

PURPOSE

An inherited mutation in KRAS (LCS6-variant or rs61764370) results in altered control of the KRAS oncogene. We studied this biomarker's correlation to anti-EGFR monoclonal antibody (mAb) therapy response in patients with metastatic colorectal cancer.

EXPERIMENTAL DESIGN

LCS6-variant and KRAS/BRAF mutational status was determined in 512 patients with metastatic colorectal cancer treated with salvage anti-EGFR mAb therapy, and findings correlated with outcome. Reporters were tested in colon cancer cell lines to evaluate the differential response of the LCS6-variant allele to therapy exposure.

RESULTS

In this study, 21.2% (109 of 512) of patients with metastatic colorectal cancer had the LCS6-variant (TG/GG), which was found twice as frequently in the BRAF-mutated versus the wild-type (WT) group (P=0.03). LCS6-variant patients had significantly longer progression-free survival (PFS) with anti-EGFR mAb monotherapy treatment in the whole cohort (16.85 vs. 7.85 weeks; P=0.019) and in the double WT (KRAS and BRAF) patient population (18 vs. 10.4 weeks; P=0.039). Combination therapy (mAbs plus chemotherapy) led to improved PFS and overall survival (OS) for nonvariant patients, and brought their outcome to levels comparable with LCS6-variant patients receiving anti-EGFR mAb monotherapy. Combination therapy did not lead to improved PFS or OS for LCS6-variant patients. Cell line studies confirmed a unique response of the LCS6-variant allele to both anti-EGFR mAb monotherapy and chemotherapy.

CONCLUSIONS

LCS6-variant patients with metastatic colorectal cancer have an excellent response to anti-EGFR mAb monotherapy, without any benefit from the addition of chemotherapy. These findings further confirm the importance of this mutation as a biomarker of anti-EGFR mAb response in patients with metastatic colorectal cancer, and warrant further prospective confirmation.

Anti-EGFR monoclonal antibodies for treatment of colorectal cancers: development of cetuximab and panitumumab

Over the last decade, anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs) have been firmly established as essential drugs for the treatment of metastatic colorectal cancer (CRC). Cetuximab and panitumumab have been approved by American and European drug agencies. This review aims at exploring the main outcomes of clinical studies performed during their clinical development, from phase I to III trials, and hence at giving a comprehensive review of the scientific rational and up-to-date evidence sustaining the use of these drugs. Many areas are still under active investigation such as administration schedules, their efficacy in comparison with bevacizumab, their role in adjuvant therapy, molecular predictors, and management of side effects.

Standard chemotherapy with cetuximab for treatment of colorectal cancer

AIM: To review and assess the evidence related to cetuximab treatment in metastatic colorectal cancer (mCRC) with regard to KRAS status.

METHODS: PubMed, EMBASE, Cochrane database and American Society of Clinical Oncology meeting abstracts were searched for randomized controlled trials (RCTs) reporting the effect of KRAS status on efficacy of chemotherapy regimen with or without cetuximab in mCRC. Baseline information such as sex and age was summarized from the included studies. Hazard ratios of progression-free survival (PFS) and overall survival (OS) as well as objective response based on KRAS status were extracted for analysis.

RESULTS: A total of 8 RCTs with 6780 patients were included. The combined analysis showed that cetuximab failed to improve the OS and PFS in patients with mCRC. However, in subgroup analysis, the pooled data showed that addition of cetuximab to irinotecan containing chemotherapy regimen was sufficient to improve OS and PFS in wild-type KRAS mCRC patients, but not in patients with mutant-type KRAS. The addition of cetuximab increased the incidence of adverse events such as diarrhea, rash, skin toxicity/rash, and nausea and vomiting. There was no significant publication bias existing in the included studies.

CONCLUSION: The clinical benefit of cetuximab was only confirmed in patients with wild-type KRAS. KRAS status could be considered a biomarker of efficacy of cetuximab.