Overexpression of epidermal growth factor type-1 receptor (EGF-R1) in cervical cancer: Implications for Cetuximab-mediated therapy in recurrent/metastatic disease

Small molecule inhibitors of the VEGF and tyrosine kinase for the treatment of cervical cancer

Cervical cancer accounts for most deaths due to cancer in women, majorly in developing nations. The culprit behind this disease is the human papillomavirus (HPV) which accounts for more than 90% of cervical cancer cases. The viral strains produce proteins that favor the knocking down of the apoptosis process and continuous growth of cells in the cervix leading to tumor growth. Proangiogenic growth factors, such as fibroblast growth factor (FGF), vascular endothelial growth factor (VEGF), angiopoietins, and other endothelial growth factors (EGF), are secreted by tumor cells and the surrounding microenvironment, which further advances the development of cancer. The extracellular domain of receptor tyrosine kinases is employed by ligands (like VEGF and EGF) to engage and activate them by inducing receptor dimerization, which facilitates the cascade impact of these factors. The tyrosine kinase domains of each receptor autophosphorylate each other, activating the receptor and initiating signaling cascades that promote angiogenesis, migration, proliferation, and survival of endothelial cells. Cancer cells benefit from its modified signaling pathways, which cause oncogenic activation. Upon early cervical cancer detection, the second-line therapy strategy involves blocking the signaling pathways with VEGF and small molecule tyrosine kinase inhibitors (TKIs). This review paper highlights the genesis of cervical cancer and combating it using VEGF and tyrosine kinase inhibitors by delving into the details of the currently available inhibitors. Further, we have discussed the inhibitor molecules that are currently in various phases of clinical trials. This paper will surely enhance the understanding of cervical cancer and its treatment approaches and what further interventions can be done to alleviate the disease currently serving as a major health burden in the developing world.

Enhancement of Chemotherapy Efficacy in Cervical Cancer via MAPK Pathway Inhibition by Osimertinib

Addressing recurrent cervical cancer poses a substantial challenge. Osimertinib, an FDA-approved EGFR inhibitor, has emerged as a promising option. Our study examined its potential to enhance paclitaxel's efficacy against cervical cancer. Osimertinib effectively hindered cancer cell growth and induced apoptosis across multiple cell lines. Combined with paclitaxel, it exhibited synergy in suppressing cervical cancer cells. Importantly, osimertinib's inhibitory effect was EGFR-independent; it targeted Mnk phosphorylation, reducing eIF4E activity. In mice, the combined osimertinib-paclitaxel treatment surpassed individual drugs in inhibiting cancer growth. These preclinical findings suggest osimertinib's repurposing as a means to improve paclitaxel's effectiveness in cervical cancer treatment.

Near-Infrared Fluorescence Imaging of EGFR-Overexpressing Tumors in the Mouse Xenograft Model Using scFv-IRDye800CW and Cetuximab-IRDye800CW

EGFR (epidermal growth factor receptor) is overexpressed in a variety of human cancers (including squamous cell carcinoma of head and neck, colon cancer, and some breast cancers) and therefore is regarded as an ideal target for cancer therapy or imaging purposes. In the current study, we produced a scFv-based near-infrared probe (called cet.Hum.scFv-IRDye-800CW) and evaluated its ability in recognizing and imaging of EGFR-overexpressing tumors in a mouse model. Like the molecular probe consisting of its parental antibody (cetuximab, an FDA-approved monoclonal antibody) and IRD800CW, cet.Hum.scFv-IRDye-800CW was able to recognize EGFR-overexpressing tumors in mice. cet.Hum.scFv-IRDye-800CW was found to be superior to the cetuximab-based probe in imaging of mouse tumors. The tumor-to-background ratio and blood clearance rate were higher when cet.Hum.scFv-IRDye-800CW was used as an imaging probe.

Updates on systemic therapy for cervical cancer

Cervical cancer is one of the most common cancers in the world both in terms of incidence and mortality, more so important in low- and middle-income countries. Surgery and radiotherapy remain the backbone of treatment for non-metastatic cervical cancer, with significant improvement in survival provided by addition of chemotherapy to radiotherapy. Survival as well as quality of life is improved by chemotherapy in metastatic disease. Platinum-based chemotherapy with/without bevacizumab is the mainstay of treatment for metastatic disease and has shown improvement in survival. The right combinations and sequence of treatment modalities and medicines are still evolving. Data regarding the molecular and genomic biology of cervical cancer have revealed multiple potential targets for treatment, and several new agents are presently under evaluation including targeted therapies, immunotherapies and vaccines. This review discusses briefly the current standards, newer updates as well as future prospective approaches in systemic therapies for cervical cancer.

A systematic review and meta-analysis of the prevalence of therapeutic targets in cervical cancer

Cervical Cancer (CC) is a significantly prevalent disease in developing countries. Currently, targeted therapies are not a primary standard of care in CC. This information could be crucial for developing directed therapies and patient screening for biomarkers that would allow personalised treatment of CC. This systematic review aimed to estimate the prevalence of potential therapeutic targets such as the epidermal growth factor receptor (EGFR) and the PI3K/Akt/mTOR and Ras/Raf/MAPK pathways in patients with CC, identified through genomic and non-genomic testing. Studies were identified through an ad-hoc search strategy from the available on MEDLINE (Ovid), CENTRAL, LILACS, SCOPUS, through the Clinical Trial registry on Clinicaltrials.gov, International Clinical Trials Registry Platform, RENIS (Argentine National Registry of Health Research) and grey literature sources. We included 74 studies which represented a total pool of 7,862 participants. Forty-five studies informed mutations of EGFR, with a combined positivity rate of 53% (95%CI: 45%-60%; I2 = 95%). Twenty studies informed the presence of mutations in PIK3CA with a combined positivity rate of 30% (95%CI: 21%-39%; I2 = 96%). Twenty-three studies reported a mutation in Ras, with a combined positivity rate of 14% (95%CI: 8%-21%; I2 = 95%). Raf mutations were informed in six studies. Six studies informed the presence of Akt mutations, two studies informed mTOR mutations and only one study reported mutations of MAPK. The most frequently described therapeutic targets were EGFR, and the PIK3CA and Ras pathways, though inconsistency in positivity rates was significant. Our study did not allow the identification of any specific clinical characteristics that might explain the observed heterogeneity. Despite the overall good quality of the included studies, the applicability of these results to patients' general population with CC is still unclear.

Vascular endothelial growth factor (VEGF) targeting therapy for persistent, recurrent, or metastatic cervical cancer

BACKGROUND

Cervical cancer ranks as the fourth leading cause of death from cancer in women. Historically, women with metastatic or recurrent cervical cancer have had limited treatment options. New anti-angiogenesis therapies, such as vascular endothelial growth factor (VEGF) targeting agents, offer an alternative strategy to conventional chemotherapy; they act by inhibiting the growth of new blood vessels, thereby restricting tumour growth by blocking the blood supply.

OBJECTIVES

To assess the benefits and harms of VEGF targeting agents in the management of persistent, recurrent, or metastatic cervical cancer.

SEARCH METHODS

We performed searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, online registers of clinical trials, and abstracts of scientific meetings up until 27 May 2020.

SELECTION CRITERIA

We examined randomised controlled trials (RCTs) that evaluated the use of VEGF targeting agents alone or in combination with conventional chemotherapy or other VEGF targeting agents.

DATA COLLECTION AND ANALYSIS

Three review authors independently screened the results of search strategies, extracted data, assessed risk of bias, and analysed data according to the standard methods expected by Cochrane. The certainty of evidence was assessed via the GRADE approach.

MAIN RESULTS

A total of 1634 records were identified. From these, we identified four studies with a total of 808 participants for inclusion. We also identified two studies that were awaiting classification and nine ongoing studies. Bevacizumab plus chemotherapy versus chemotherapy Treatment with bevacizumab plus chemotherapy may result in lower risk of death compared to chemotherapy alone (hazard ratio (HR) 0.77, 95% confidence interval (CI) 0.62 to 0.95; 1 study, 452 participants; low-certainty evidence). However, there are probably more specific adverse events when compared to chemotherapy alone, including gastrointestinal perforations or fistulae (risk ratio (RR) 18.00, 95% CI 2.42 to 133.67; 1 study, 440 participants; moderate-certainty evidence); serious thromboembolic events (RR 4.5, 95% CI 1.55 to 13.08; 1 study, 440 participants; moderate-certainty evidence); and hypertension (RR 13.75, 95% CI 5.07 to 37.29; 1 study, 440 participants; moderate-certainty evidence). There may also be a higher incidence of serious haemorrhage (RR 5.00, 95% CI 1.11 to 22.56; 1 study, 440 participants; low-certainty evidence). In addition, the incidence of serious adverse events is probably higher (RR 1.44, 95% CI 1.16 to 1.79; 1 study, 439 participants; moderate-certainty evidence). The incremental cost-effectiveness ratio was USD 295,164 per quality-adjusted life-year (1 study, 452 participants; low-certainty evidence). Cediranib plus chemotherapy versus chemotherapy Treatment with cediranib plus chemotherapy may or may not result in similar risk of death when compared to chemotherapy alone (HR 0.94, 95% CI 0.53 to 1.65; 1 study, 69 participants; low-certainty evidence). We found very uncertain results for the incidences of specific adverse events, including gastrointestinal perforations or fistulae (RR 3.27, 95% CI 0.14 to 77.57; 1 study, 67 participants; very low-certainty evidence); serious haemorrhage (RR 5.45, 95% CI 0.27 to 109.49; 1 study, 67 participants; very low-certainty evidence); serious thromboembolic events (RR 3.41, 95% CI 0.14 to 80.59; 1 study, 60 participants; very low-certainty evidence); and serious hypertension (RR 0.36, 95% CI 0.02 to 8.62; 1 study, 67 participants; very low-certainty evidence). In addition, there may or may not be a similar incidence of serious adverse events compared to chemotherapy alone (RR 1.15, 95% CI 0.75 to 1.78; 1 study, 67 participants; low-certainty evidence). Apatinib plus chemotherapy or chemotherapy/brachytherapy versus chemotherapy or chemotherapy/brachytherapy Treatment with apatinib plus chemotherapy or chemotherapy/brachytherapy may or may not result in similar risk of death compared to chemotherapy alone or chemotherapy/brachytherapy alone (HR 0.90, 95% CI 0.51 to 1.60; 1 study, 52 participants; low-certainty evidence). However, hypertension events may occur at a higher incidence as compared to chemotherapy alone or chemotherapy/brachytherapy alone (RR 5.14, 95% CI 1.28 to 20.73; 1 study, 52 participants; low-certainty evidence). Pazopanib plus lapatinib versus lapatinib Treatment with pazopanib plus lapatinib may result in higher risk of death compared to lapatinib alone (HR 2.71, 95% CI 1.16 to 6.31; 1 study, 117 participants; low-certainty evidence). We found very uncertain results for the incidences of specific adverse events, including gastrointestinal perforations or fistulae (RR 2.00, 95% CI 0.19 to 21.59; 1 study, 152 participants; very low-certainty evidence); haemorrhage (RR 2.00, 95% CI 0.72 to 5.58; 1 study, 152 participants; very low-certainty evidence); and thromboembolic events (RR 3.00, 95% CI 0.12 to 72.50; 1 study, 152 participants; very low-certainty evidence). In addition, the incidence of hypertension events is probably higher (RR 12.00, 95% CI 2.94 to 49.01; 1 study, 152 participants; moderate-certainty evidence). There may or may not be a similar incidence of serious adverse events as compared to lapatinib alone (RR 1.45, 95% CI 0.94 to 2.26; 1 study, 152 participants; low-certainty evidence). Pazopanib versus lapatinib Treatment with pazopanib may or may not result in similar risk of death as compared to lapatinib (HR 0.96, 95% CI 0.67 to 1.38; 1 study, 152 participants; low-certainty evidence). We found very uncertain results for the incidences of specific adverse events, including gastrointestinal perforations or fistulae (RR 1.03, 95% CI 0.07 to 16.12; 1 study, 150 participants; very low-certainty evidence); haemorrhage (RR 1.03, 95% CI 0.31 to 3.40; 1 study, 150 participants; very low-certainty evidence); and thromboembolic events (RR 3.08, 95% CI 0.13 to 74.42; 1 study, 150 participants; very low-certainty evidence). In addition, the incidence of hypertension events is probably higher (RR 11.81, 95% CI 2.89 to 48.33; 1 study, 150 participants; moderate-certainty evidence). The risk of serious adverse events may or may not be similar as compared to lapatinib (RR 1.31, 95% CI 0.83 to 2.07; 1 study, 150 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

We found low-certainty evidence in favour of the use of bevacizumab plus chemotherapy. However, bevacizumab probably increases specific adverse events (gastrointestinal perforations or fistulae, thromboembolic events, hypertension) and serious adverse events. We found low-certainty evidence that does not support the use of cediranib plus chemotherapy, apatinib plus chemotherapy, apatinib plus chemotherapy/brachytherapy, or pazopanib monotherapy. We found low-certainty evidence suggesting that pazopanib plus lapatinib worsens outcomes. The VEGF inhibitors apatinib and pazopanib may increase the probability of hypertension events.

Nimotuzumab Site-Specifically Labeled with 89Zr and 225Ac Using SpyTag/SpyCatcher for PET Imaging and Alpha Particle Radioimmunotherapy of Epidermal Growth Factor Receptor Positive Cancers

Simple Summary

Monoclonal antibodies (IgG) are excellent probes for targeting cell surface receptors for imaging and therapeutic applications. These theranostic agents are often developed by randomly conjugating radioisotopes/drugs/chelators to the primary amine of lysine or the sulfhydryl groups of cysteine on the antibody. Random conjugation often alters the properties of the antibody. We have site-specifically radiolabeled nimotuzumab an anti-epidermal growth factor receptor (EGFR) monoclonal antibody with 89Zr and 225Ac using SpyTag: ∆N-SpyCatcher for positron emission tomography (PET) imaging and alpha particle radiotherapy, and evaluated these agents in a model of EGFR-positive triple negative breast cancer (TNBC). Nimotuzumab-SpyTag-∆N-SpyCatcher constructs showed improved binding in vitro compared with randomly conjugated constructs. 89Zr-nimotuzumab-SpyTag-∆N-SpyCatcher specifically delineated EGFR-positive xenograft in vivo using microPET/CT imaging. Compared with control treatment groups, 225Ac-nimotuzumab-SpyTag-∆N-SpyCatcher more than doubled the survival of mice bearing EGFR-positive MDA-MB-231 TNBC xenograft. This work highlights a facile method to site-specifically radiolabel antibodies using SpyTag: ∆N-SpyCatcher.

Abstract

To develop imaging and therapeutic agents, antibodies are often conjugated randomly to a chelator/radioisotope or drug using a primary amine (NH₂) of lysine or sulfhydryl (SH) of cysteine. Random conjugation to NH₂ or SH groups can require extreme conditions and may affect target recognition/binding and must therefore be tested. In the present study, nimotuzumab was site-specifically labeled using ∆N-SpyCatcher/SpyTag with different chelators and radiometals. Nimotuzumab is a well-tolerated anti-EGFR antibody with low skin toxicities. First, ΔN-SpyCatcher was reduced using tris(2-carboxyethyl)phosphine (TCEP), which was followed by desferoxamine-maleimide (DFO-mal) conjugation to yield a reactive ΔN-SpyCatcher-DFO. The ΔN-SpyCatcher-DFO was reacted with nimotuzumab-SpyTag to obtain stable nimotuzumab-SpyTag-∆N-SpyCatcher-DFO. Radiolabeling was performed with ⁸⁹Zr, and the conjugate was used for the in vivo microPET imaging of EGFR-positive MDA-MB-468 xenografts. Similarly, ∆N-SpyCatcher was conjugated to an eighteen-membered macrocyclic chelator macropa-maleimide and used to radiolabel nimotuzumab-SpyTag with actinium-225 (²²⁵Ac) for in vivo radiotherapy studies. All constructs were characterized using biolayer interferometry, flow cytometry, radioligand binding assays, HPLC, and bioanalyzer. MicroPET/CT imaging showed a good tumor uptake of ⁸⁹Zr-nimotuzumab-SpyTag-∆N-SpyCatcher with 6.0 ± 0.6%IA/cc (n = 3) at 48 h post injection. The EC₅₀ of ²²⁵Ac-nimotuzumab-SpyTag-∆N-SpyCatcher and ²²⁵Ac-control-IgG-SpyTag-∆N-SpyCatcher against an EGFR-positive cell-line (MDA-MB-468) was 3.7 ± 3.3 Bq/mL (0.04 ± 0.03 nM) and 18.5 ± 4.4 Bq/mL (0.2 ± 0.04 nM), respectively. In mice bearing MDA-MB-468 EGFR-positive xenografts, ²²⁵Ac-nimotuzumab-SpyTag-∆N-SpyCatcher significantly (p = 0.0017) prolonged the survival of mice (64 days) compared to ²²⁵Ac-control IgG (28.5 days), nimotuzumab (28.5 days), or PBS-treated mice (30 days). The results showed that the conjugation and labeling using SpyTag/∆N-SpyCatcher to nimotuzumab did not significantly (p > 0.05) alter the receptor binding of nimotuzumab compared with a non-specific conjugation approach. ²²⁵Ac-nimotuzumab-SpyTag-∆N-SpyCatcher was effective in vitro and in an EGFR-positive triple negative breast cancer xenograft model.

Molecular landscape of recurrent cervical cancer

Cervical cancer (CC) is a major gynecological problem in developing and underdeveloped countries. Despite the significant advancement in early detection and treatment modalities, several patients recur. Moreover, the molecular mechanisms responsible for CC recurrence remains obscure. The patients with CC recurrence often show poor prognosis and significantly high mortality rates. The clinical management of recurrent CC depends on treatment history, site, and extent of the recurrence. Owing to poor prognosis and limited treatment options, recurrent CC often presents a challenge to the clinicians. Several in vitro, in vivo, and patient studies have led to the identification of the critical molecular changes responsible for CC recurrence. Both aberrant genetic and epigenetic modifications leading to altered cell signaling pathways have been reported to impact CC recurrence. Researchers are currently trying to dissect the molecular pathways in CC and translate these findings for better management of disease. This article attempts to review the existing knowledge of disease relapse, accompanying challenges, and associated molecular players in CC.

Clinical study of nimotuzumab combined with concurrent radiochemotherapy for treatment of locally advanced cervical cancer

PURPOSE

Nimotuzumab is a humanized monoclonal antibody that targets the epidermal growth factor receptor (EGFR) to inhibit tumor growth. Nimotuzumab has demonstrated desirable therapeutic activity in various types of tumors. However, the benefit of nimotuzumab for the treatment of cervical cancer is not entirely clear. The present study aimed to investigate the effects of nimotuzumab in the presence of CCRT in the first-line treatment of locally advanced cervical cancer (LACC).

METHODS

The therapeutic efficacy and side effects of nimotuzumab combined with concurrent radiochemotherapy (CCRT) were retrospectively assessed in inoperable patients with LACC (stage IIb-IIIb) who were treated using CCRT with or without nimotuzumab.

RESULTS

The complete response rate of study group was significantly better than control group (78.3% vs 50%, P=0.035). The difference in median progression-free survival (PFS) in the two groups was statistically significan (not reach vs 27 months, P=0.037). Multivariate comparisons of prognostic factors in the two groups indicated that both the Fédération Internationale de Gynécologie et d'Obstétrique (FIGO) stage and combined nimotuzumab treatment affected PFS (P<0.05). Although generally tolerable, grade 3-4 toxicities including leukopenia (P=0.025) and hemoglobin (P=0.026) reduction were more frequent in the control group than those in the study group.

CONCLUSION

These data suggest that combining nimotuzumab with CCRT for the treatment of LACC resulted in extended PFS and higher complete remission rates, without an increased incidence of adverse events.

Kaempferia parviflora Extract Inhibits STAT3 Activation and Interleukin-6 Production in HeLa Cervical Cancer Cells

Kaempferia parviflora (KP) has been reported to have anti-cancer activities. We previously reported its effects against cervical cancer cells and continued to elucidate the effects of KP on inhibiting the production and secretion of interleukin (IL)-6, as well as its relevant signaling pathways involved in cervical tumorigenesis. We discovered that KP suppressed epidermal growth factor (EGF)-induced IL-6 secretion in HeLa cells, and it was associated with a reduced level of Glycoprotein 130 (GP130), phosphorylated signal transducers and activators of transcription 3 (STAT3), and Mcl-1. Our data clearly showed that KP has no effect on nuclear factor kappa B (NF-κB) localization status. However, we found that KP inhibited EGF-stimulated phosphorylation of tyrosine 1045 and tyrosine 1068 of EGF receptor (EGFR) without affecting its expression level. The inhibition of EGFR activation was verified by the observation that KP significantly suppressed a major downstream MAP kinase, ERK1/2. Consistently, KP reduced the expression of Ki-67 protein, which is a cellular marker for proliferation. Moreover, KP potently inhibited phosphorylation of STAT3, Akt, and the expression of Mcl-1 in response to exogenous IL-6 stimulation. These data suggest that KP suppresses EGF-induced production of IL-6 and inhibits its autocrine IL-6/STAT3 signaling critical for maintaining cancer cell progression. We believe that KP may be a potential alternative anti-cancer agent for suppressing cervical tumorigenesis.

Investigation of natural phenanthrenes and the antiproliferative potential of juncusol in cervical cancer cell lines

BACKGROUND

Phenanthrenes isolated from Juncus species possess different biological activities, including antiproliferative and antimigratory effects.

PURPOSE

In this study, nine phenanthrenes isolated from the roots of Juncus inflexus were investigated for their antiproliferative activity on several gynecological cancer cell lines, using non-cancerous cells as controls.

METHODS

Antiproliferative activities of the compounds were determined by means of MTT assay. Flow cytometry was used for cell cycle analysis and determination of mitotic cells. Activities of caspase-3, -8, and -9 were detected by colorimetric kits. Tubulin polymerization was followed by kinetic absorbance determination. Action on tumor cell migration was described using wound healing assay. Western blot assays were used to determine apoptosis-related factors at protein level.

RESULTS

Among the compounds tested, juncusol exhibited the most substantial antiproliferative effect against cervical cancer HeLa cells. It was also revealed that juncusol has a distinct growth inhibitory effect in cervical cancer cell lines of various HPV status: it was highly active in HPV type 18-positive HeLa cells, while it was inactive in HPV type 16-positive SiHa and CaSki cells. Cell cycle analysis showed an increase in G2/M and subG1 cell populations after juncusol treatment. Caspase-3, -8, and -9 were detected to be activated by juncusol in HeLa cells, indicating that juncusol induces apoptotic cell death. Moreover, juncusol inhibited tubulin polymerization, as well as EGFR activation, suggesting two possible additional mechanisms that may account for juncusol's inducing a G2/M-phase cell cycle arrest and inhibiting cell migration.

CONCLUSION

These results suggest that juncusol is a potent antiproliferative agent against HPV-18 related cervical cancer and may be considered as a lead compound for the development of innovative anticancer agents.

Therapeutic potential of nimotuzumab PEGylated-maytansine antibody drug conjugates against EGFR positive xenograft

Nimotuzumab is a humanized anti-epidermal growth factor receptor I (EGFR) monoclonal antibody. We have developed antibody drug conjugates (ADCs) with nimotuzumab conjugated to PEGylated-maytansine (PEG₆-DM1). We generated conjugates with low (nimotuzumab-PEG₆-DM1-Low: DAR = 3.5) and high (nimotuzumab-PEG₆-DM1-High: DAR = 7.3) drug to antibody ratios (DAR). Quality control was performed using UV spectrophotometry, size exclusion HPLC, bioanalyzer, biolayer interferometry (BLI), and flow cytometry in EGFR-positive DLD-1, MDA-MB-468 (high density EGFR), and HT-29 (very low EGFR density) cells. Control antibody drug conjugates were developed using a human anti-maltose binding protein (MBP) antibody. BLI showed that the binding of nimotuzumab-PEG₆-DM1-Low and nimotuzumab-PEG₆-DM1-High was slightly but significantly affected by conjugation of the drug (nimotuzumab K_D 0.89 ± 0.02 nM < nimotuzumab-PEG₆-DM1-Low K_D 1.94 ± 0.02 nM < nimotuzumab-PEG₆-DM1-High K_D 3.75 ± 0.03 nM). In vitro cytotoxicity was determined following incubation of cells with the immunoconjugates and IC₅₀ values were determined. Nimotuzumab-PEG₆-DM1-Low and nimotuzumab-PEG₆-DM1-High were used to treat EGFR positive KRAS mutant DLD-1 colorectal cancer xenograft. DLD-1 cells were transduced with a red fluorescent protein (iRFP702) to allow the use of near infrared imaging (NIR) for tumor response monitoring. In vitro potency correlated with the number of drugs on antibody, with nimotuzumab-PEG₆-DM1-High showing higher activity than nimotuzumab-PEG₆-DM1-Low. Three doses (15 mg/kg) of the ADCs prolonged the survival of DLD-1-iRFP-702 tumor bearing mice as monitored by NIR. Nimotuzumab-PEG₆-DM1-Low resulted in 4/6 complete cure while nimotuzumab-PEG₆-DM1-High resulted in 2/5 complete cure. The novel ADCs were very effective in a colorectal cancer model in vivo.

Preclinical Evaluation of 111In-Labeled PEGylated Maytansine Nimotuzumab Drug Conjugates in EGFR-Positive Cancer Models

Epidermal growth factor receptor I (EGFR) is overexpressed in most cancers of epithelial origin. Antibody drug conjugates (ADCs) with PEGylated-maytansine (PEG-DM1) show promise in vitro and in vivo. However, in vivo biodistribution data for ADCs with PEG-DM1 have not been reported. Development of methods to understand the real-time in vivo behavior of these ADCs is needed to move these compounds to the clinic. Methods: Here we have used noninvasive small-animal SPECT/CT imaging and ex vivo biodistribution to understand the in vivo behavior of PEG₆-DM1 ADCs. We developed nimotuzumab ADCs conjugated to PEG₆-DM1. We generated immunoconjugates with low (nimotuzumab-PEG₆-DM1-Low) and high (nimotuzumab-PEG₆-DM1-High) drug-to-antibody ratios. The drug-to-antibody of nimotuzumab-PEG₆-DM1-Low and nimotuzumab-PEG₆-DM1-High was 3.5 and 7.3, respectively. Quality control was performed using ultraviolet spectrophotometry, size-exclusion high-performance liquid chromatography, bioanalyzer, biolayer interferometry, and flow cytometry in EGFR-positive DLD-1 cells. These immunoconjugates were conjugated with DOTA and radiolabeled with ¹¹¹In. The in vitro binding and internalization rates of ¹¹¹In-nimotuzumab, ¹¹¹In-nimotuzumab-PEG₆-DM1-Low, and ¹¹¹In-nimotuzumab-PEG₆-DM1-High were characterized. Furthermore, the pharmacokinetics, biodistribution, and imaging characteristics were evaluated in normal and DLD-1 tumor-bearing mice. Results: Flow cytometry and biolayer interferometry showed a trend toward decreasing EGFR affinity with increasing number of PEG₆-DM1 on the antibody. Despite the lower overall cellular binding of the PEG₆-DM1 radioimmunoconjugates, internalization was higher for PEG₆-DM1 ADCs than for the non-PEGylated ADC in the following order: ¹¹¹In-nimotuzumab-PEG₆-DM1-High > ¹¹¹In-nimotuzumab-PEG₆-DM1-Low > ¹¹¹In-nimotuzumab. Nuclear uptake of ¹¹¹In-nimotuzumab-PEG₆-DM1-High was 4.4-fold higher than ¹¹¹In-nimotuzumab. Pharmacokinetics and biodistribution showed that ¹¹¹In-nimotuzumab-PEG₆-DM1-High had the slowest blood and whole-body clearance rate. Uptake in DLD-1 tumors of ¹¹¹In-nimotuzumab was similar to ¹¹¹In-nimotuzumab-PEG₆-DM1-Low but was significantly higher than for ¹¹¹In-nimotuzumab-PEG₆-DM1-High. Tumor-to-background ratios for ¹¹¹In-nimotuzumab and ¹¹¹In-nimotuzumab-PEG₆-DM1-Low were higher than for ¹¹¹In-nimotuzumab-PEG₆-DM1-High. Conclusion: The results show that conjugation of multiple PEG₆-DM1 reduces the affinity for EGFR in vitro. However, the reduced affinity is counteracted by the high internalization rate of constructs with PEG₆-DM1 ADCs in vitro. The decreased affinity resulted in low tumor uptake of ¹¹¹In-nimotuzumab-PEG₆-DM1-High, with a slow overall whole-body clearance rate. These data provide insights for evaluating the pharmacokinetics and normal -tissue toxicity and in determining dosing rate of PEGylated ADCs.

Application of chimeric antigen receptor-engineered T cells in ovarian cancer therapy

Due to the critical role of T cells in the immune surveillance of ovarian cancer, adoptive T-cell therapies are receiving increased attention as an immunotherapeutic approach for ovarian cancer. Chimeric antigen receptors (CARs), constructed by incorporating the single-chain Fv fragment to a T-cell signaling domain such as CD3 ζ or Fc receptor γ chain, endow T cell with nonmajor histocompatibility complex-restricted specificity. Dual specificity, trans-signaling CARs and affinity-tuned single-chain Fv fragment have broadened the applicability of CAR-engineered T-cell therapy and may be considered preferential to T cell receptor T-cell therapy in clinical care. As new insights into the CAR-engineered T cells have emerged over the last decade, we review the development of CAR T-cell therapy and discuss the progress and safety concerns regarding its translation from basic research into clinical care of ovarian cancer.

89Zr-nimotuzumab for immunoPET imaging of epidermal growth factor receptor I

Rationale

Epidermal growth factor receptor (EGFR) upregulation is associated with enhanced proliferation and drug resistance in a number of cancers. Nimotuzumab is a humanized monoclonal antibody with high affinity for EGFR. The objective of this study was to determine if ⁸⁹Zr-DFO-nimotuzumab could be suitable for human use as a PET probe for quantifying EGFR in vivo.

Methods

To evaluate the pharmacokinetics, biodistribution, microPET imaging, radiation dosimetry, and normal tissue toxicity in tumor and non-tumor bearing mice of ⁸⁹Zr-desferoxamine-nimotuzumab (⁸⁹Zr-DFO-nimotuzumab) of a product prepared under GMP conditions. Nimotuzumab was conjugated to DFO and radiolabeled with ⁸⁹Zr. ⁸⁹Zr-DFO-nimotuzumab was characterized by in vitro gel-electrophoresis, biolayer interferometry (BLI) and flow cytometry. ⁸⁹Zr-DFO-nimotuzumab was evaluated in vivo by microPET and ex vivo by biodistribution in healthy and EGFR-positive tumor bearing mice.

Results

Flow cytometry with A431 cells showed no significant difference in the dissociation constant of nimotuzumab (13 ± 2 nM) compared with DFO-nimotuzumab (17 ± 4 nM). PET imaging in mice xenografts showed persistently high tumor uptake with the highest uptake obtained in DLD-1 xenograft (18.3 %IA/cc) at 168 hp.i. The projected human effective dose was low and was 0.184 mSv/MBq (0.679 rem/mCi) in females and 0.205 mSv/MBq (0.757 rem/mCi) in males. There was no apparent normal tissue toxicity as shown by cell blood counts and blood biochemistry analyses at 168-fold and 25-fold excess of the projected human radioactive and mass dose of the agent.

Conclusion

⁸⁹Zr-DFO-nimotuzumab had low organ absorbed dose and effective dose that makes it suitable for potential human use.

Near infrared fluorescence imaging of EGFR expression in vivo using IRDye800CW-nimotuzumab

Nimotuzumab is a humanized anti-epidermal growth factor receptor (EGFR) monoclonal antibody that is approved in many countries for the treatment of EGFR-positive cancers. Near infrared (NIR) fluorescent dye-labeled antibodies represent an attractive class of image-guided surgical probes because of their high specificity, tumor uptake, and low dissociation from tumor cells that express the antigen. In this study, we developed a NIR fluorescent dye-labeled nimotuzumab immunoconjugate, IRDye800CW-nimotuzumab, and evaluated in vitro binding with EGFR-positive cells, in vivo tumor uptake by NIR fluorescent imaging, and ex vivo biodistribution. There was no difference in binding between nimotuzumab and IRDye800CW-nimotuzumab to EGFR-positive cells. In mice bearing EGFR-positive xenografts, IRDye800CW-nimotuzumab uptake peaked at 4 days post injection and slowly decreased thereafter with high levels of accumulation still observed at 28 days post injection. In EGFR-positive xenografts, IRDye800CW-nimotuzumab showed more than 2-fold higher uptake in tumors compared to IRDye800CW-cetuximab. In addition, liver uptake of IRDye800CW-nimotuzumab was two-fold lower than cetuximab. The lower liver uptake of IRDye800CW-nimotuzumab could have implications on the selected dose for clinical trials of the immunoconjugate. In summary, this study shows that nimotuzumab is a good candidate for NIR fluorescent imaging and image-guided surgery.

High-efficiency lysis of cervical cancer by allogeneic NK cells derived from umbilical cord progenitors is independent of HLA status

Down-regulation of HLA in tumor cells, low numbers and dysfunctionality of NK cells are commonly observed in patients with end-stage cervical cancer. Adoptive transfer of high numbers of cytotoxic NK cells might be a promising treatment approach in this setting. Here, we explored the cytotoxic efficacy on ten cervical cancer cell lines of activated allogeneic NK cells from two sources, i.e., peripheral blood (PBNK) with and without cetuximab (CET), a tumor-specific monoclonal antibody directed against EGFR, or derived from umbilical cord blood (UCB-NK). Whereas CET monotherapy was ineffective against the panel of cervical cancer cell lines, irrespective of their EGFR expression levels and despite their RAS^wt status, it significantly enhanced the in vitro cytotoxic efficacy of activated PBNK (P = 0.002). Equally superior cytotoxicity over activated PBNK alone was achieved by UCB-NK (P < 0.001). Both PBNK- and UCB-NK-mediated cytotoxic activity was dependent on the NK-activating receptors natural killer group 2, member D receptor (NKG2D) and DNAX accessory molecule-1 (DNAM-1) (P < 0.05) and unrelated to expression levels of the inhibitory receptors HLA-E and/or HLA-G. Most strikingly, whereas the PBNK’s cytotoxic activity was inversely correlated with HLA-ABC levels (P = 0.036), PBNK + CET and UCB-NK cytotoxicity were entirely independent of HLA-ABC expression. In conclusion, this study provides a rationale to initiate a clinical trial for cervical cancer with adoptively transferred allogeneic NK cells, employing either UCB-NK or PBNK + CET for EGFR-expressing tumors. Adoptive transfer of UCB-NK might serve as a generally applicable treatment for cervical cancer, enabled by HLA-, histology- and HPV-independent killing mechanisms.

EGFR Promoter Methylation, EGFR Mutation, and HPV Infection in Chinese Cervical Squamous Cell Carcinoma

Therapy strategy toward epidermal growth factor receptor (EGFR) inhibition in cervical cancer has been ongoing. EGFR promoter methylation status and EGFR tyrosine kinase inhibitor-sensitive mutations in cervical cancer may be significant for clinical outcome prediction using anti-EGFR treatment. In this study, EGFR tyrosine kinase inhibitor-sensitive mutations, EGFR exons 18, 19, and 21 mutations, were detected by sequencing in a total of 293 Chinese cervical squamous cell carcinoma tissue samples. EGFR promoter methylation status was detected by an EGFR asymmetric PCR and hybridization-fluorescence polarization assay and sequencing in 293 Chinese cervical squamous cell carcinoma tissue samples. High-risk human papillomavirus (HPV) genotypes in 293 Chinese cervical squamous cell carcinoma tissue samples were detected by an asymmetric GP5+/6+ PCR and hybridization-fluorescence polarization assay. No EGFR exons 18, 19, and 21 mutations were detected, EGFR promoter methylation status was identified in 98 samples, and HPV 16 infection was the first frequent HPV genotype. The methylated EGFR promoter was identified most frequently in cervical squamous cell carcinoma samples with HPV 16 infection (53.4%). Statistical significant difference of EGFR promoter methylation prevalence was found between HPV 16 and other HPV genotypes (P<0.01). This study suggested that there was no EGFR tyrosine kinase inhibitor-sensitive mutation in EGFR exons 18, 19, and 21 in Chinese cervical squamous cell carcinoma tissue samples. EGFR promoter methylation was common and it might be associated with HPV 16 infection in Chinese cervical squamous cell carcinoma. The results provided a novel understanding and an applicable pharmacogenomic tool for individualized management of cervical cancer patients.

Immunotherapy and targeted therapy for cervical cancer: an update

The prognosis of patients with metastatic cervical cancer is poor with a median survival of 8-13 months. Despite the potency of chemotherapeutic drugs, this treatment is rarely curative and should be considered palliative only. In the last few years, a better understanding of Human papillomavirus tumor-host immune system interactions and the development of new therapeutics targeting immune check points have renewed interest in the use of immunotherapy in cervical cancer patients. Moreover, next generation sequencing has emerged as an attractive option for the identification of actionable driver mutations and other markers. In this review, we provide background information on the molecular biology of cervical cancer and summarize immunotherapy studies, targeted therapies, including those with angiogenesis inhibitors and tyrosine kinase inhibitors recently completed or currently on-going in cervical cancer patients.

In vitro baselining of new pyrrolopyrimidine EGFR-TK inhibitors with Erlotinib

Epidermal growth factor receptor tyrosine kinase inhibitors are useful in treatment of non-small cell lung cancer, and show promise in combination therapy settings. Two novel chiral pyrrolopyrimidines have been baselined towards Erlotinib, Lapatinib and Dasatinib using in vitro cellular studies and ADME profiling. One of these, (S)-2-((6-(4-(hydroxymethyl)-2-methoxyphenyl)-7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)-2-phenylethan-1-ol, was more active than Erlotinib in lung and breast cancer cell models. The compound also had promising activity towards ovarian cancer cell lines, while low activity was seen towards cells of haematological origin. ADME profiling revealed good solubility, higher metabolic stability than Erlotinib and no inhibitory effect towards the hERG voltage-gated ion channel. Investigation of inhibitory potency towards 6 CYP isoforms generally revealed low inhibitory potency, but in the case of CYP3A4, a substrate dependent inhibition was noted using testosterone as substrate (IC50: 12.5μM). No cellular or gene toxicity was noted for the compounds or products of phase I metabolism. However, permeability studies using Caco-2 cells revealed a high efflux ratio. Further experiments using ABC transporter inhibitors revealed that the pyrrolopyrimidines are actively transported by the breast cancer resistant protein and P-glycoprotein transporters, which might prevent their further development into drugs.

ErbB-targeted CAR T-cell immunotherapy of cancer

Chimeric antigen receptor (CAR) based immunotherapy has been under development for the last 25 years and is now a promising new treatment modality in the field of cancer immunotherapy. The approach involves genetically engineering T cells to target malignant cells through expression of a bespoke fusion receptor that couples an HLA-independent antigen recognition domain to one or more intracellular T-cell activating modules. Multiple clinical trials are now underway in several centers to investigate CAR T-cell immunotherapy of diverse hematologic and solid tumor types. The most successful results have been achieved in the treatment of patients with B-cell malignancies, in whom several complete and durable responses have been achieved. This review focuses on the preclinical and clinical development of CAR T-cell immunotherapy of solid cancers, targeted against members of the ErbB family.

[Targeted therapy in locally and metastatic recurrent cervical cancers]

Doublet chemotherapy with cisplatin is the reference for the treatment of recurrent cervical cancer. However, those tumors are little chemo-sensitive and overall survival remains poor. Moreover, because of pelvic irradiation, toxicities, especially hematologic toxicities, are increased and require a drug dose reduction. Finally, these treatments are rarely effective in radiation areas. Given all these elements, the development of new therapies is a prominent issue. This article reviews the results of the major targeted therapies in cervical cancer. Anti-EGFRs are disappointing despite of a strong biological rational. On the other hand, bevacizumab is the first targeted therapy to show a significant increase of overall survival. A major effort must be made in translational research for a better understanding of tumor biology of these tumors.

Growth factor progranulin contributes to cervical cancer cell proliferation and transformation in vivo and in vitro

OBJECTIVE

The growth factor progranulin (PGRN) is overexpressed in a number of tumors. We aimed to investigate the expression and role of PGRN in cervical cancer tumorigenesis.

METHODS

PGRN expression and secretion was assessed in cells and normal and cancerous cervical tissues by Western blot analysis, ELISA or immunohistochemistry. The role of PGRN in cervical carcinogenesis was explored by cell-proliferation, colony-formation and tumor-growth assays. We assessed the role of PGRN-mediated signaling in the cervical cell with specific inhibitors.

RESULTS

PGRN expression was upregulated in cervical cancer cell lines and tissue. PGRN promoted the transformation of human cervical mucosa epithelial H8 cells in vitro and tumor formation in vivo. Knockdown of PGRN expression in cervical cancer cells in vivo decreased cell proliferation and slowed tumor growth. PGRN stimulated cervical cell proliferation, and transformation was mediated, at least in part, by Akt and Erk signaling.

CONCLUSIONS

PGRN is overexpressed in cervical cancer and promotes the malignant growth and transformation of cervical cells. Therefore, PGRN plays a critical role in carcinogenesis of cervical cancer and shows promise for therapeutic strategies for cervical cancer.

Oropharyngeal cancers: relationship between epidermal growth factor receptor alterations and human papillomavirus status

High-risk human papillomavirus (HR-HPV), particularly type 16, is now recognised as a causative agent in a subset of oropharyngeal squamous cell carcinomas (OPSCCs). These tumours are on the increase and generally have a better prognosis than their HPV negative counterparts. This raises the question of de escalation therapy to reduce long term consequences in a younger cohort of patients with a long life expectancy. Several clinical trials with anti-epidermal growth factor receptor (EGFR) therapies, particularly cetuximab, are ongoing. Few data exist on the relationship between EGFR and HPV induced oropharyngeal cancers. We summarise the main studies in relation to EGFR alterations (gene copy number, protein expression and mutations) and the impact on prognosis of HPV positive tumours that express high levels of EGFR. We also discuss the opportunity of targeting this pathway in light of recent studies.

Emerging biological treatments for uterine cervical carcinoma

Cervical cancer is the third most common cancer worldwide, and the development of new diagnosis, prognostic, and treatment strategies is a major interest for public health. Cisplatin, in combination with external beam irradiation for locally advanced disease, or as monotherapy for recurrent/metastatic disease, has been the cornerstone of treatment for more than two decades. Other investigated cytotoxic therapies include paclitaxel, ifosfamide and topotecan, as single agents or in combination, revealing unsatisfactory results. In recent years, much effort has been made towards evaluating new drugs and developing innovative therapies to treat cervical cancer. Among the most investigated molecular targets are epidermal growth factor receptor and vascular endothelial growth factor (VEGF) signaling pathways, both playing a critical role in cervical cancer development. Studies with bevacizumab or VEGF receptor tyrosine kinase have given encouraging results in terms of clinical efficacy, without adding significant toxicity. A great number of other molecular agents targeting critical pathways in cervical malignant transformation are being evaluated in preclinical and clinical trials, reporting preliminary promising data.

In the current review, we discuss novel therapeutic strategies which are being investigated for the treatment of advanced cervical cancer.

The combination of the antiviral agent cidofovir and anti-EGFR antibody cetuximab exerts an antiproliferative effect on HPV-positive cervical cancer cell lines' in-vitro and in-vivo xenografts

Cervical carcinoma remains a leading cause of female mortality worldwide and over 90% of these tumors contain the human papillomavirus (HPV) genome. Cross-talk between the epidermal growth factor receptor and HPV has been reported and is implicated in tumor progression. The combination of the antiviral compound cidofovir (Cd) with the monoclonal antibody antiepidermal growth factor receptor cetuximab (Cx) was evaluated. HPV-positive (HeLa and Me180) and HPV-negative (C33A, H460 and A549) human cancer cell lines were incubated with Cd (1-10 μg/ml) and/or Cx (10 or 50 μg/ml). The antitumor effect of the combination was assessed in vitro using a clonogenic survival assay, cell cycle analysis, and phospho-H2AX level. Tumor growth delay was assayed in vivo using xenograft models. A pan-genomic analysis was carried out to identify the genes expressed differentially in untreated HeLa HPV-positive cells versus cells treated by the Cd-Cx combination. The Cd-Cx combination inhibited proliferation in all the cell lines tested. The association of Cd and Cx exerted a synergistic activity on HPV-positive but not on HPV-negative cell lines. The combination delayed tumor growth of HPV-positive tumors in vivo; however, no efficacy was reported on HPV-negative C33A xenografts nor on cell lines treated by single-drug therapy. The combination induced an S-phase arrest associated with an enhanced level of the double-strand break in Me180 and HeLa cell lines. Gene profiling assays showed a significant differential modulation of genes in HeLa cell lines treated with the combination involving the EGR-1 transcription factor. The current data support a synergistic antiproliferative action of the Cd-Cx combination on HPV-related cervical tumors.

Immunohistochemical analysis of thymic carcinoma focusing on the possibility of molecular targeted and hormonal therapies

OBJECTIVE

Thymic carcinoma is a rare mediastinal malignant tumor, and in many patients, the tumor is detected in an inoperable advanced stage. Even when chemotherapy is administered to such patients, the patients show a poor response. We investigated new biomarkers of therapeutic molecular targets.

METHODS

This study included 44 patients diagnosed and treated for primary thymic epithelial tumors at Showa University Northern Yokohama Hospital, Showa University Hospital, and Showa University Fujigaoka Hospital from 2003 to 2011. We investigated new biomarkers of therapeutic molecular targets, such as the peroxisome proliferator-activated receptor γ (PPARγ), insulin-like growth factor 1 receptor (IGF1R), epidermal growth factor receptor (EGFR), estrogen receptor (ER), progesterone receptor (PgR), androgen receptor (AR), human epidermal growth factor type 2 (HER2)/neu, CD44, and L-type amino acid transporter 1 (LAT1), in thymic tumors.

RESULT

Immunohistochemical analysis showed that the PPARγ positivity rate in thymic carcinoma was 32 %, which was significantly higher than that in thymoma (4 %). The IGF1R positivity rate in thymic carcinoma was 73 %, which was significantly higher than that in thymoma (27 %).

CONCLUSION

Therefore, by examining the expressions of PPARγ and IGF1R, it would be possible to identify therapy-responsive patients and to improve results of thymic carcinoma treatment.

Treatment of metastatic cervical cancer: future directions involving targeted agents

Cervical cancer is the third most common cause of female cancer mortality, and it remains a major health problem in populations with limited economic resources. Metastatic disease or recurrent lesions not amenable to radical local excision or regional radiation have a poor prognosis, and are treated with palliative platinum-based chemotherapy. There are few effective therapeutic options for patients who progressed after first-line chemotherapy. Future advances in the treatment of metastatic or recurrent disease may rely on more effective and better-tolerated therapies, and molecularly driven targeted agents could represent an attractive option. Inhibition of tumor angiogenesis and epidermal growth factor receptor directed therapies have focused the most recent clinical research efforts. A thorough molecular characterization of cervical cancer remains crucial for a rationale implementation of targeted agents and companion biomarkers. Alternative clinical trial designs may also be necessary to optimize the clinical development of new drugs for metastatic cervical cancer.

Hyperactivation of constitutively dimerized oncogenic EGF receptors by autocrine loops

The epidermal growth factor (EGF) receptor (EGFR) has a key role in normal embryonic development, adult tissue homeostasis and many pathological processes, in particular tumour formation. Aberrant EGFR activation occurs in many cancer types, and inhibition of this receptor is a promising anti-tumour strategy. Besides overexpression of the wild-type receptor, mutated oncogenic EGFR variants are often associated with malignant transformation. In human non-small-cell lung cancers, kinase mutants of the EGFR are rather common. Human glioblastoma often express the truncated EGFRvIII version as well as other dimerized and permanently activated mutants of the receptor, which are considered as tumour drivers. Similarly, the mutated and dimerized EGFR variant Xiphophorus melanoma receptor kinase (Xmrk) is causative for the development of malignant pigment cell tumours in medaka and Xiphophorus melanoma models. It is generally believed that oncogenic receptors that are active due to dimerizing mutations are ligand independent. Here, we show that different EGFR variants from fish and human efficiently induce autocrine loops by inducing EGFR ligands such as amphiregulin and HB-EGF. Importantly, the pre-dimerized oncogenic EGFR versions Xmrk from Xiphophorus and human EGFR(C600F), though already active in absence of ligands, respond to ligand stimulation with enhanced oncogenic signalling. In summary, our data show that autocrine or paracrine loops are still acting on pre-dimerized oncogenic EGFRs and contribute to their pro-tumorigenic signalling.

Flexible targeting of ErbB dimers that drive tumorigenesis by using genetically engineered T cells

Pharmacological targeting of individual ErbB receptors elicits antitumor activity, but is frequently compromised by resistance leading to therapeutic failure. Here, we describe an immunotherapeutic approach that exploits prevalent and fundamental mechanisms by which aberrant upregulation of the ErbB network drives tumorigenesis. A chimeric antigen receptor named T1E28z was engineered, in which the promiscuous ErbB ligand, T1E, is fused to a CD28 + CD3ζ endodomain. Using a panel of ErbB-engineered 32D hematopoietic cells, we found that human T1E28z⁺ T cells are selectively activated by all ErbB1-based homodimers and heterodimers and by the potently mitogenic ErbB2/3 heterodimer. Owing to this flexible targeting capability, recognition and destruction of several tumor cell lines was achieved by T1E28⁺ T cells in vitro, comprising a wide diversity of ErbB receptor profiles and tumor origins. Furthermore, compelling antitumor activity was observed in mice bearing established xenografts, characterized either by ErbB1/2 or ErbB2/3 overexpression and representative of insidious or rapidly progressive tumor types. Together, these findings support the clinical development of a broadly applicable immunotherapeutic approach in which the propensity of solid tumors to dysregulate the extended ErbB network is targeted for therapeutic gain.

Monoclonal antibodies in gynecological cancer: a critical point of view

During the last decades, several improvements in treating gynecological malignancies have been achieved. In particular, target therapies, mostly monoclonal antibodies, have emerged as an attractive option for the treatment of these malignancies. In fact, various molecular-targeted agents have been developed for a variety of malignancies with the objective to interfere with a precise tumor associated receptor, essential for cancer cell survival or proliferation, blocking its function, of the cancer cells. Alternatively, monoclonal antibodies have been developed to block immune suppression or enhance functions of immune effector cells. So far, several monoclonal antibodies have been tested for clinical efficacy for the treatment of gynecological cancers. Antibodies against Vascular Endothelial Growth Factor (VEGF) and Epidermal Growth Factor Receptor (EGFR) have been used in different neoplasms such as ovarian and cervical cancer. Catumazumab, a bivalent antibody against CD3 and EpCAM, is effective in the treatment of neoplastic ascites. Other antibodies are peculiar for specific cancer-associated antigen such as Oregovomab against CA125 or Farletuzumab against the folate receptor. Here we describe the preclinical and clinical experience gained up to now with monoclonal antibodies in tumors of the female genital tract and trace future therapeutic and research venues.

Efficient blockade of Akt signaling is a determinant factor to overcome resistance to matuzumab

BACKGROUND

Clinical studies have shown antineoplastic effectiveness of monoclonal antibodies (MAbs) against EGFR for different indications. Several MAbs directed to EGFR were developed recently, such as matuzumab, but there is still lack of information on preclinical data on its combination with chemo-radiation. Thus, the present study intended to examine the molecular pathways triggered by matuzumab alone or associated to chemo-radiotherapy in gynecological cell lines and its impact on cell growth and signaling.

RESULTS

Combination of matuzumab with radiation and cisplatin did not enhance its cytostatic effects on A431, Caski and C33A cells (high, intermediate and low EGFR expression, respectively) in clonogenic assays, when compared to controls. The lack of effect was mediated by persistent signaling through EGFR due to its impaired degradation. In spite of the fact that matuzumab inhibited phosphorylation of EGFR, it had no effect upon cell viability. To analyze which downstream molecules would be involved in the EGFR signaling in the presence of matuzumab, we have tested it in combination with either PD98059 (MAPK inhibitor), or LY294002 (PI3K inhibitor). Matuzumab exhibited a synergic effect with LY294002, leading to a reduction of Akt phosphorylation that was followed by a decrease in A431 and Caski cells survival. The combination of PD98059 and matuzumab did not show the same effect suggesting that PI3K is an important effector of EGFR signaling in matuzumab-treated cells. Nonetheless, matuzumab induced ADCC in Caski cells, but not in the C33A cell line, suggesting that its potential therapeutic effects in vitro are indeed dependent on EGFR expression.

CONCLUSIONS

Matuzumab combined with chemoradiation did not induce cytotoxic effects on gynecological cancer cell lines in vitro, most likely due to impaired EGFR degradation. However, a combination of matuzumab and PI3K inhibitor synergistically inhibited pAkt and cell survival, suggesting that the use of PI3K/Akt inhibitors could overcome intrinsic resistance to matuzumab in vitro. Altogether, data presented here can pave the way to a rational design of clinical strategies in patients with resistant profile to anti-EGFR inhibitors based on combination therapy.

Phase II trial of cetuximab in the treatment of persistent or recurrent squamous or non-squamous cell carcinoma of the cervix: a Gynecologic Oncology Group study

PURPOSE

The Gynecologic Oncology Group (GOG) conducted a phase II trial to assess the efficacy and tolerability of the anti-EGFR antibody cetuximab, in persistent or recurrent carcinoma of the cervix.

PATIENTS AND METHODS

Eligible patients had cervical cancer, measurable disease, and GOG performance status ≤2. Treatment consisted of cetuximab 400 mg/m(2) initial dose followed by 250 mg/m(2) weekly until disease progression or prohibitive toxicity. The primary endpoints were progression-free survival (PFS) at 6 months and response. The study used a 2-stage group sequential design.

RESULTS

Thirty-eight patients were entered with 3 exclusions, leaving 35 evaluable for analysis. Thirty-one patients (88.6%) received prior radiation as well as either 1 (n=25, 71.4%) or 2 (n=10) prior cytotoxic regimens. Twenty-four patients (68.6%) had a squamous cell carcinoma. Grade 3 adverse events possibly related to cetuximab included dermatologic (n=5), GI (n=4), anemia (n=2), constitutional (n=3), infection (n=2), vascular (n=2), pain (n=2), and pulmonary, neurological, vomiting and metabolic (n=1 each). No clinical responses were detected. Five patients (14.3%; two-sided 90% CI, 5.8% to 30%) survived without progression for at least 6 months. The median PFS and overall survival (OS) times were 1.97 and 6.7 months, respectively. In this study, all patients with PFS at 6 months harbored tumors with squamous cell histology.

CONCLUSION

Cetuximab is well tolerated but has limited activity in this population. Cetuximab activity may be limited to patients with squamous cell histology.

EGFR gene amplification is related to adverse clinical outcomes in cervical squamous cell carcinoma, making the EGFR pathway a novel therapeutic target

Background:

The aim of this study was to investigate the patterns of epidermal growth factor receptor (EGFR) overexpression, EGFR gene amplification, and the presence of activating mutations in the tyrosine kinase domain of this gene in squamous cell carcinomas and adenocarcinomas/adenosquamous carcinomas of the uterine cervix.

Methods:

The EGFR expression, amplification, and mutation in cervical carcinomas were assessed by immunohistochemistry, fluorescence in situ hybridisation, and PCR–SSCP, respectively, and correlated with clinical data collected by a retrospective chart review. A functional assessment was performed by inactivating EGFR in cervical cancer cells with the potent inhibitor AG1478.

Results:

Immunohistochemical analysis revealed that 6 out of 59 (10.2%) cervical squamous cell carcinomas showed significant amplification of the EGFR locus, whereas none of the 52 adeno/adenosquamous cell carcinomas had detectable EGFR amplification (P<0.05). The EGFR amplification significantly correlated with shorter overall survival (P=0.001) in cervical squamous cell carcinomas. Multivariate analysis showed that EGFR gene amplification was an independent prognostic factor for overall survival (P=0.011). None of the squamous cell carcinomas (0%: 0 out of 32) had detectable oncogenic mutations in EGFR exons 18 through 21. The frequencies of KRAS and BRAF mutations were very low in both squamous and adeno/adenosquamous cell carcinomas. Sensitivity of cervical cancer cells to AG1478 depended on the presence of EGFR overexpression. AG1478-induced EGFR inactivation in cell lines with EGFR overexpression significantly suppressed tumour development and progression in a mouse xenograft model.

Conclusion:

Our data suggest that EGFR signalling is important in a subset of cervical squamous cell carcinomas and that anti-EGFR therapy may benefit patients who carry the 7p11.2 amplicon in their tumours.

Expression of phosphorylated histone H2AX (γ-H2AX) in normal and neoplastic squamous epithelia of the uterine cervix: an immunohistochemical study with epidermal growth factor receptor

The histone γ-H2AX is a marker of activated DNA damage and is overexpressed in different cancers and their precursor lesions, indicating a role in oncogenic transformation. Epidermal growth factor receptor (EGFR) is overexpressed in many kinds of epithelial neoplasms. This study aimed to determine whether immunohistochemical expression of γ-H2AX is involved in the progression of the morphological spectrum from normal squamous cervical epithelia (NE, n=33) to cervical intraepithelial neoplasia (CIN; CIN1, n=9; CIN2/3, n=33) and cervical invasive squamous cell carcinoma (ISCC, n=33), whether γ-H2AX expression follows the pattern of proliferation of atypical squamous cells as shown by EGFR immunoreactivity, and whether it is correlated with clinicopathologic variables in ISCC. Immunostaining for both the factors was scored semiquantitatively for moderate and strong intensities. Gamma-H2AX and EGFR expression, respectively, increased from NE and CIN1 to CIN2/3 and ISCCs significantly (P=0.0001, respectively). Gamma-H2AX reactivity was found in the nuclei of the cells of the upper epithelial levels and the cells of basal/parabasal type in variable quantities in NE and CIN; expression of γ-H2AX was seen in the nuclei of ISCC including keratinizing cells in horn pearls. EGFR staining was mainly membranous and noted in basal/parabasal cells in NE and atypically proliferating keratinocytes in CIN and nonkeratinizing cells of ISCC. In addition, immature squamous metaplasias were decorated by the antibodies used. Immunoscores for γ-H2AX and EGFR, respectively, did not differ between International Federation of Gynecology and Obstetrics stages I and II, keratinizing and nonkeratinizing ISCC, and CIN2/3 and ISCC. However, expression patterns were different for both the factors, suggesting their involvement in different biological mechanisms, with regard to γ-H2AX apart from proliferation. Overexpression of γ-H2AX in CIN2/3 and ISCC of the uterine cervix reflects the neoplastic transformation of cervical squamous epithelia in reaction to increased DNA-damage and supports the classification of dysplasia into low-grade squamous intraepithelial lesions and high-grade squamous intraepithelial lesions.

Epidermal growth factor receptor as a biomarker for cervical cancer

This review focuses on the different modes of expression of the epidermal growth factor receptor (EGFR). All methods used to assess EGFR expression are critically analyzed and insights into the use of inhibitors of EGFR for treatment of cervical cancer are discussed. Currently, expression of EGFR as a biomarker for prognosis or for treatment of cervical cancer is not defined for clinical use.

Expression of epidermal growth factor receptor and vascular endothelial growth factor in vaginal squamous cell cancer

OBJECTIVE

Primary invasive squamous cell carcinoma of the vagina is a rare neoplasm. Investigations concerning the potential of new therapeutic targets are limited.

STUDY DESIGN

A total of 34 patients with primary invasive squamous cell carcinoma of the vagina was identified, who were treated at our institution between 1994 and 2008. Epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) expression was assessed using immunohistochemistry from paraffin-embedded tissue blocks.

RESULTS

EGFR was expressed in 33 of 34 (97.1%) and VEGF was expressed in 12 of 34 cases (35.3%). There was no statistically significant relationship between clinicopathologic parameters (clinical stage, grading, tumor size), patient survival, and EGFR and VEGF expression.

CONCLUSION

VEGF was moderate and EGFR was frequently expressed in invasive squamous cell carcinoma of the vagina. In our sample size, immunohistochemical staining was not statistically significantly associated with prognosis.

Differential expression of ANXA6, HSP27, PRDX2, NCF2, and TPM4 during uterine cervix carcinogenesis: diagnostic and prognostic value

Background:

Cytology-based diagnostics of squamous cervical cancer (SCC) precursor lesions is subjective and can be improved by objective markers.

Methods:

IHC-based analysis of ANXA6, HSP27, peroxiredoxin 2 (PRDX2), NCF2, and tropomyosin 4 (TPM4) during SCC carcinogenesis.

Results:

Expression of ANXA6, HSP27, PRDX2, and NCF2 in the cytoplasm of dysplastic cells increased from cervical intraepithelial neoplasia 2/3 (CIN2/3) to microinvasive cancer. Invasive SCC showed lower expression of TPM4 than CIN and normal epithelium. CIN2/3 with the highest sensitivity and specificity differed from normal epithelium by cytoplasmic expression of HSP27. Patients with cytoplasmic HSP27 expression in SCC deviating from that observed in normal epithelium had worse relapse-free (P=0.019) and overall (P=0.014) survival. Invasive SCC with the highest sensitivity and specificity differed from normal epithelium by expression of PRDX2 and TPM4 in the cytoplasm, from CIN2/3 by the expression of ANXA6 and TPM4 in the cytoplasm, and from microinvasive SCC by the expression of PRDX2 and ANXA6 in the cytoplasm. The number of sporadic ANXA6+ cells between the atypical cells increased from CIN2/3 to invasive SCC.

Conclusion:

Detection of expression changes of the proteins ANXA6, HSP27, PRDX2, NCF2, and TPM4 in SCC precursor lesions may aid current cytological and pathological diagnostics and evaluation of prognosis.

Phase II, Open-Label Study of Pazopanib or Lapatinib Monotherapy Compared With Pazopanib Plus Lapatinib Combination Therapy in Patients With Advanced and Recurrent Cervical Cancer

Purpose

Pazopanib and lapatinib are tyrosine kinase inhibitors that target vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit or epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2/neu), respectively. In cervical cancer, EGFR and HER2/neu overexpression and high microvascular density correlate with survival.

Patients and Methods

Patients with measurable stage IVB persistent/recurrent cervical carcinoma not amenable to curative therapy and at least one prior regimen in the metastatic setting were randomly assigned in a ratio of 1:1:1 to pazopanib at 800 mg once daily, lapatinib at 1,500 mg once daily, or lapatinib plus pazopanib combination therapy (lapatinib at 1,000 mg plus pazopanib at 400 mg once daily or lapatinib at 1,500 mg plus pazopanib at 800 mg once daily). Therapy continued until progression or withdrawal because of adverse events (AEs). Primary end point was progression-free survival (PFS), and secondary end points were overall survival (OS), response rate (RR), and safety. The futility boundary was crossed at the planned interim analysis for combination therapy compared with lapatinib therapy, and the combination was discontinued.

Results

Of 230 patients enrolled, 152 were randomly assigned to the monotherapy arms: pazopanib (n = 74) or lapatinib (n = 78). Most patients (62%) had recurrent cancer. Pazopanib improved PFS (hazard ratio [HR], 0.66; 90% CI, 0.48 to 0.91; P = .013) and OS (HR, 0.67; 90% CI, 0.46 to 0.99; P = .045). Median OS was 50.7 weeks and 39.1 weeks and RRs were 9% and 5% for pazopanib and lapatinib, respectively. The only grade 3 AE > 10% was diarrhea (11% pazopanib and 13% lapatinib). Grade 4 AEs were 9% (lapatinib) and 12% (pazopanib).

Conclusion

This study confirms the activity of antiangiogenesis agents in advanced and recurrent cervical cancer and demonstrates the benefit of pazopanib based on the prolonged PFS and favorable toxicity profile.