Changes in HER3 expression profiles between primary and recurrent gynecological cancers.

BACKGROUND: Human epidermal growth factor receptor-3 (HER3) is a member of the epidermal growth factor receptor family of receptor tyrosine kinases, and its overexpression is associated with inferior prognosis in several cancers. However, it is unclear whether HER3 expression status changes in tumor tissue at recurrence. Therefore, this study aimed to evaluate the changes in HER3 expression between primary and recurrent status in gynecological cancers. METHODS: This retrospective study used matched-pair tissues of gynecological cancer patients at initial diagnosis and at recurrence. Immunohistochemical (IHC) scores of 3 + or 2 + were termed "HER3-high", while IHC scores of 1 + or 0 were designated as "HER3-low/zero". RESULTS: A total of 86 patients (40 with ovarian cancers, 32 with endometrial cancers, and 14 with cervical cancers) were included in this study. In ovarian cancer, 67.5% and 80.0% of the patients received a HER3-high at initial and recurrent diagnosis, respectively. The H-score was significantly increased at recurrence (p = 0.004). The proportion of HER3-high endometrial cancer patients increased from 46.9% at initial diagnosis to 68.8% at recurrence, and the H-score tended to increase at recurrence (p = 0.08). The fraction of HER3-high-rated cervical cancer patients remained unchanged at 85.7% both at initial and recurrent diagnosis. The discordance rate of HER3 expression detection in initial and recurrent diagnosis samples was 27.5%, 53.1%, and 14.3% for ovarian, endometrial, and cervical cancers, respectively. Ovarian and endometrial cancers with a HER3-high recurrent score tended to show shorter median survival time than those with a HER3-low/zero recurrent rating. CONCLUSION: Our findings suggest that, in main types of gynecological cancers, the proportion of patients having a HER3-high score increased from initial to recurrent diagnosis.

Comprehensive screening for drugs that modify radiation-induced immune responses.

BACKGROUND: Combination therapy based on radiotherapy and immune checkpoint inhibitors (ICIs) was recently reported as effective for various cancers. The radiation-induced immune response (RIIR) is an essential feature in ICI-combined radiotherapy; however, the effects of drugs used concomitantly with RIIR remain unclear. We screened for drugs that can modify RIIR to understand the mutual relationship between radiotherapy and combined drugs in ICI-combined radiotherapy. METHODS: We established a high-throughput system with reporter gene assays for evaluating RIIR, focusing on factors acting downstream of the STING-IRF pathway, which can stimulate cancer cells, T cells, and dendritic cells. We further quantified the effects of 2595 drugs, including those approved by the Food and Drug Administration, on RIIR in vitro. RESULTS: The reporter assay results correlated well with the expression of immune response proteins such as programmed death-ligand 1. This high-throughput system enabled the identification of drugs including cytotoxic agents, molecular-targeted agents, and other agents that activate or suppress RIIR. CONCLUSIONS: Our study provides an encyclopedic catalogue of clinically approved drugs based on their effect on RIIR. In ICIs combined radiotherapy, activation of STING-IFN may improve the therapeutic effect and our result could form a biological basis for further clinical trials combining radiotherapy with ICIs.

Poor Treatment Outcomes with Second-Line Chemotherapy in Advanced Synovial Sarcoma.

INTRODUCTION: Synovial sarcoma (SS) predominantly affects adolescents and young adults. Doxorubicin with or without ifosfamide therapy is the standard first-line treatment for unresectable or metastatic SS. However, there is no standard second-line chemotherapy regimen. The purpose of the current study was to evaluate the outcomes of second-line chemotherapy for patients with SS. METHODS: We retrospectively evaluated the outcomes of 61 patients with unresectable or metastatic SS who had received first-line chemotherapy at our institution between 1997 and 2017. Patients who received second-line chemotherapy were included in the analysis. Outcomes of the chemotherapy were evaluated. RESULTS: Among the 61 patients treated with first-line chemotherapy, we identified 32 patients who received second-line chemotherapy. Most patients (62.5%) were under 40 years of age. Regarding second-line chemotherapy regimens, 6 (18.8%) patients were treated with doxorubicin with/without ifosfamide, 6 (18.8%) with ifosfamide and etoposide, 4 (12.5%) with docetaxel and gemcitabine, 5 (15.6%) with pazopanib, 2 (6.2%) with trabectedin, and 1 (3.1%) with eribulin. The overall response rate according to the Response Evaluation Criteria in Solid Tumors for all patients was 9.4%. Eleven patients (34.3%) achieved disease-control for >6 months. The median follow-up duration was 15.2 months. The 1-year progression-free and overall survival rates were 33.1% and 67.1%, respectively. CONCLUSION: Our exploratory study revealed that the response rate of second-line chemotherapy regimens for patients with SS was 9.4%. Therefore, there is an urgent need to develop more active therapeutic regimens for SSs.

Potential utility of a longitudinal relative dose intensity of molecularly targeted agents in phase 1 dose-finding trials.

Phase 1 trials of molecularly targeted agents (MTA) often do not use toxicity data beyond the first cycle of treatment to determine a recommended phase 2 dose (RP2D). We investigated the potential utility of longitudinal relative dose intensity (RDI) that may be a better new way of determining a more accurate RP2D as a lower dose that is presumably more tolerable over the long term without compromising efficacy. All consecutive patients who were initially treated using a single MTA at the conventional RP2D or at one level lower dose (OLLD) of that RP2D in 9 phase 1 trials sponsored by the National Cancer Institute were included. The associations between longitudinal RDI, time to first progression, and response rate were analyzed. The RDI of the conventional RP2D group were maintained a rate of ≥70% throughout 10 cycles, and were higher than those of the OLLD group, although in both groups the RDI gradually decreased with additional treatment cycles. The RP2D group was similar to the OLLD group with respect to time to first progression and response rate. In both groups, however, the decreasing RDI over time was significantly associated with shorter time to first disease progression; therefore, the longitudinal RDI, which takes into account lower grade toxicity occurrences, may be useful in determining a more desirable dose to use in phase 2 and 3 studies.

Trends in the development of MET inhibitors for hepatocellular carcinoma.

Hepatocellular carcinoma is the third most common cause of cancer-related deaths worldwide. The multikinase inhibitor sorafenib has improved survival and is now considered the standard of care; however, the benefits are still disappointing, and thus, new effective treatments are required. In human hepatocellular carcinoma, MET, which is encoded by the HGFR gene, is activated by amplification, overexpression or mutation, and it has recently emerged as a possible therapeutic target in various tumors including hepatocellular carcinoma. In fact, some drugs targeting the HGF/MET axis are currently under investigation in clinical trials. Here, we review the role of MET and trends in the development of MET inhibitors for hepatocellular carcinoma.

Predicting Trabectedin Efficacy in Soft Tissue Sarcoma: Inflammatory Biomarker Analysis.

BACKGROUND/AIM: Trabectedin is used as a treatment for advanced-stage soft tissue sarcomas (STSs), particularly liposarcoma and leiomyosarcoma. Aside from its direct effect on tumor cells, trabectedin can affect the immune system in the tumor microenvironment. This study aimed to evaluate whether inflammatory biomarkers predict trabectedin efficacy in STSs. PATIENTS AND METHODS: We retrospectively reviewed the clinical features and outcomes of patients with STS treated with trabectedin at our institution between 2016 and 2020. The neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), and systemic inflammation response index (SIRI=neutrophil × monocyte/lymphocyte) were calculated based on the blood samples obtained prior to trabectedin treatment initiation. Analyses of overall survival (OS) and progression-free survival (PFS) were performed according to various factors. RESULTS: Of the 101 patients identified, 54 had L-sarcoma (leiomyosarcoma: 30; liposarcoma: 24), and 47 had other types of STSs. Elevated SIRI, NLR, PLR, LMR, and C-reactive protein (CRP) were associated with worse PFS (p<0.001, p=0.008, p=0.027, p=0.013, and p<0.001, respectively) according to the results of the univariate analysis. Multivariate analysis showed that elevated SIRI, other histology, and CRP were associated with poor PFS (p=0.007, p=0.008, and p=0.029, respectively). In addition, the multivariate analysis of OS showed that SIRI was an independent prognostic factor (hazard ratio=2.16, p=0.006). CONCLUSION: Pretreatment SIRI can be considered a biomarker for the prognostic prediction of patients with STS treated with trabectedin.

Development of a Detection System for ESR1 Mutations in Circulating Tumour DNA Using PNA-LNA-Mediated PCR Clamping.

Although circulating tumour DNA (ctDNA)-based next-generation sequencing (NGS) is a less invasive method for assessing ESR1 mutations that are essential mechanisms of endocrine therapy resistance in patients with oestrogen receptor-positive breast cancer, adequate amounts of DNA are required to assess polyclonal ESR1 mutations. By combining a peptide nucleic acid and locked nucleic acid polymerase chain reaction (PNA-LNA PCR) clamping assay, we have developed a novel detection system to screen for polyclonal ESR1 mutations in ctDNA. A validation assay was prospectively performed on clinical samples and compared with the NGS results. The PNA-LNA PCR clamp assay was validated using six and four blood samples in which ESR1 mutations were detected by NGS and no mutations were detected, respectively. The PNA-LNA assay results were comparable with those of NGS. We prospectively assessed the concordance between the PNA-LNA PCR clamp method and NGS. Using the PNA-LNA PCR clamp method, ESR1 mutations were detected in 5 out of 18 samples, including those in which mutations were not detected by NGS due to small amounts of ctDNA. The PNA-LNA PCR clamping method is a highly sensitive and minimally invasive assay for polyclonal ESR1 mutation detection in the ctDNA of patients with breast cancer.

Phase II Trial of Nivolumab in Metastatic Rare Cancer with dMMR or MSI-H and Relation with Immune Phenotypic Analysis (the ROCK Trial).

PURPOSE: Mismatch repair deficiency (dMMR)/microsatellite instability-high (MSI-H) are positive predictive markers for immune checkpoint inhibitors. However, data on the activity of nivolumab in advanced dMMR/MSI-H rare cancers and more accurate biomarkers are worth exploring. PATIENTS AND METHODS: We conducted a multicenter phase II, open-label, single-arm clinical trial to explore the effectiveness and safety of nivolumab monotherapy in patients with advanced rare cancers with dMMR/MSI-H, in parallel with immune phenotype analysis, to explore new biomarkers. A Bayesian adaptive design was applied. Characterization of peripheral blood mononuclear cells (PBMC) was characterized by multicolor flow cytometric analysis and CyTOF using samples collected before and after the intervention. The dMMR was identified by the complete loss of MLH1/MSH2/MSH6/PMS2. RESULTS: From May 2018 to March 2021, 242 patients were screened, and 11 patients were enrolled, of whom 10 were included in the full analysis. Median follow-up was 24.7 months (interquartile range, 12.4-31.5). Objective response rate was 60% [95% confidence interval (CI), 26.2-87.8] by central assessment and 70% (95% CI, 34.8-93.3) by local investigators. Median progression-free survival was 10.1 months (95% CI, 0.9-11.1). No treatment-related adverse events of grade 3 or higher were observed. Patients with a tumor mutation burden of ≥10/Mb showed a 100% response rate (95% CI, 47.8-100). Responders had increased T-bet+ PD-1+ CD4+ T cells in PBMC compared with nonresponders (P < 0.05). CONCLUSIONS: The trial met its primary endpoint with nivolumab, demonstrating clinical benefit in advanced dMMR/MSI-H rare solid cancers. Besides, the proportion of T-bet+ PD-1+ CD4+ T-cells may serve as a novel predictive biomarker.

Therapeutic target biomarkers of patient-derived xenograft models of gastric-type cervical adenocarcinoma.

Background: Most cervical adenocarcinomas are associated with human papillomavirus (HPV). Gastric-type cervical adenocarcinoma (GAS), an HPV-independent adenocarcinoma, shows an aggressive clinical feature, resulting in a poor prognosis. Resistance to chemotherapy poses a difficulty in managing patients with metastatic GAS. We aimed to establish patient-derived xenografts (PDXs) of tumors from two patients with GAS and evaluated protein biomarkers for drug development using immunohistochemistry. Methods: Two PDXs were established 78 and 48 days after transplanting the patient's tumor tissues into immunodeficient mice, respectively. PDX and patient's tumor samples were stained for HER2, HER3, PMS2, MSH6, PanTrk, and ARID1A to evaluate biomarkers for therapeutic targets. In addition, whole exome sequencing and RNA sequencing were performed on available samples. Results: The pathological findings in morphological features and immunohistochemical profiles from the established PDXs were similar to those from the patients' surgical tumor specimens. HER3 was overexpressed in the patient's tumors, and the corresponding PDX tumors and HER2 was weakly stained in both types of tumor samples. In all PDX and patient tumor samples, PMS2, MSH6, and ARID1A were retained, and PanTrk was not expressed. In addition, a total of 10 samples, including tumor tissue samples from 8 other GAS patients, were evaluated for HER3 expression scores, all of which were 2 + or higher. Conclusions: In summary, we evaluated biomarkers for therapeutic targets using newly established PDX models of GAS. Frequent HER3 overexpression and HER2 expression in GAS tumors suggest the possibility of new treatments for patients with GAS by targeting HER3 and HER2.

Clinical Application of Comprehensive Genomic Profiling Tests for Diffuse Gliomas.

Next-generation sequencing-based comprehensive genomic profiling test (CGPT) enables clinicians and patients to access promising molecularly targeted therapeutic agents. Approximately 10% of patients who undergo CGPT receive an appropriate agent. However, its coverage of glioma patients is seldom reported. The aim of this study was to reveal the comprehensive results of CGPT in glioma patients in our institution, especially the clinical actionability. We analyzed the genomic aberrations, tumor mutation burden scores, and microsatellite instability status. The Molecular Tumor Board (MTB) individually recommended a therapeutic agent and suggested further confirmation of germline mutations after considering the results. The results of 65/104 patients with glioma who underwent CGPTs were reviewed by MTB. Among them, 12 (18.5%) could access at least one therapeutic agent, and 5 (7.7%) were suspected of germline mutations. A total of 49 patients with IDH-wildtype glioblastoma showed frequent genomic aberrations in the following genes: TERT promoter (67%), CDKN2A (57%), CDKN2B (51%), MTAP (41%), TP53 (35%), EGFR (31%), PTEN (31%), NF1 (18%), BRAF (12%), PDGFRA (12%), CDK4 (10%), and PIK3CA (10%). Since glioma patients currently have very limited standard treatment options and a high recurrence rate, CGPT might be a facilitative tool for glioma patients in terms of clinical actionability and diagnostic value.

Impact of ALK Inhibitors in Patients With ALK-Rearranged Nonlung Solid Tumors.

PURPOSE: Anaplastic lymphoma kinase (ALK) rearrangement is a well-known driver oncogene in non-small-cell lung cancer and has also been identified in other types of tumors. However, there is limited evidence on the clinical response to ALK tyrosine kinase inhibitors (TKIs), such as alectinib and crizotinib, in rare tumors with ALK fusion. We evaluated the therapeutic effect of ALK-TKIs in rare ALK-rearranged tumors. PATIENTS AND METHODS: Between April 2012 and April 2019, clinical outcomes and characteristics of patients with ALK-rearranged nonlung solid tumors who received ALK-TKIs (alectinib and/or crizotinib) outside of clinical trials were reviewed. Expression and/or rearrangement of ALK was evaluated by immunohistochemistry, fluorescence in situ hybridization, and next-generation sequencing. The tumor response was assessed according to RECIST (version 1.1). Progression-free survival was estimated from initial ALK-TKI initiation until progression. RESULTS: We identified seven patients (inflammatory myofibroblastic tumors, n = 3; ALK-positive histiocytosis, n = 1; histiocytic sarcoma, n = 1; osteosarcoma, n = 1; and parotid adenocarcinoma, n = 1), with a median age of 17 years. Two rare ALK fusions, namely, CTNNA1-ALK and ITSN2-ALK, were identified. As initial ALK-TKI therapy, five patients received alectinib and two received crizotinib. The objective response rate for the initial ALK-TKI therapy was 85.7% (95% CI, 44 to 97), including two patients who received alectinib and achieved complete response. The median progression-free survival was 8.1 months (range, 1.7 to not estimable). There were no treatment interruptions or dose reductions because of adverse events caused by alectinib. CONCLUSION: This study highlights the potential benefit of ALK-TKIs, especially alectinib, in patients with ALK-rearranged nonlung solid tumors.

MASTER KEY Project: Powering Clinical Development for Rare Cancers Through a Platform Trial.

For rare cancers, challenges in establishing standard therapies are greater than those for major cancers, and effective methods are needed. MASTER KEY Project is a multicenter study based in Japan, with two main parts: prospective registry study and multiple clinical trials. Advanced rare cancers, cancers of unknown primary origin, and those with rare tissue subtypes of common cancers are targeted. The registry study accumulates highly reliable consecutive data that can be used for future drug development. The multiple trials are conducted simultaneously, targeting either a specific biomarker or a rare tumor type of interest. The first interim data set from the registry part presented here shows the prevalence of genetic abnormalities, response rates, survival rates, and clinical trial enrollment rates. From May 2017 to April 2019, 560 patients (mean age = 53) were enrolled in the project. Frequent cancer types included soft tissue sarcomas, neuroendocrine tumors, and central nervous system tumors. Among the 528 patients with assessable data, 69% (364/528) had next-generation sequencing tests, with 48% (176/364) harboring an "actionable" alteration. Seventy-one (13%) patients have been enrolled in one of the clinical trials, with an accrual rate of 3.94 patients/month. A descriptive analysis of biomarker-directed or non-biomarker-directed treatment survival was performed. This project is expected to accelerate development of treatments for rare cancers and show that comprehensive platform trials are an advantageous strategy.

HER3 protein expression as a risk factor for post-operative recurrence in patients with early-stage adenocarcinoma and adenosquamous carcinoma of the cervix.

Patients with cervical adenocarcinoma (AC) and adenosquamous carcinoma (ASC) have a poorer prognosis than those with squamous cell carcinoma (SCC). Erb-b2 receptor tyrosine kinase 3 (HER3) is a member of the epidermal growth factor receptor family and its expression is associated with unfavorable prognosis in several cancer types, including SCC of the cervix. As there is limited information on the prognostic value of HER3 for AC and ASC of the cervix, the present study aimed to evaluate the expression of HER3 and its impact on post-operative recurrence in patients with AC and ASC of the cervix. This retrospective study included 39 patients with early-stage AC and ASC who underwent primary surgery between January 1997 and December 2017. Immunohistochemical staining for HER3 was performed on formalin-fixed paraffin-embedded surgical specimens. The possible influence of HER3 expression on disease-free survival (DFS) was studied by using multivariate Cox regression with adjustment for established risk factors of post-operative recurrence. High expression of HER3 (HER3-high) was detected in 85.1% of cases of AC (23/27) and in 58.3% of cases of ASC (7/12). The median follow-up duration was 63.1 months and Kaplan-Meier analysis indicated that the 5-year DFS rates of patients with AC and ASC of the cervix were 56.7% in patients with HER3-high and 77.8% in patients with HER3-low (log rank, P=0.20). On multivariate analysis, HER3-high [hazard ratio (HR)=6.32, 95% CI: 1.10-36.26, P=0.039), pelvic lymph node metastasis (HR=7.61, 95% CI: 2.07-28.00, P=0.002) and vascular invasion (HR=4.28, 95% CI: 1.12-16.31, P=0.033) were indicated to be independent predictors of DFS. To date, the present study is the most comprehensive analysis to evaluate the expression of HER3 in patients with early-stage AC and ASC of the cervix. The results suggested that HER3 overexpression may be an independent risk factor for post-operative recurrence. However, these results and the prognostic value of HER3 should be confirmed in a larger sample.

Neoadjuvant chemotherapy promotes the expression of HER3 in patients with ovarian cancer.

HER3 (erbB3) signaling serves an important role in the development and chemoresistance of ovarian cancer, and is activated by chemotherapy. To evaluate the influence of neoadjuvant chemotherapy and other clinical factors on the expression of HER3, as well as to examine its role as a prognostic marker, the present study evaluated archived tissues from patients who underwent surgery for ovarian cancer between 2011 and 2018 at our hospital. Immunohistochemical staining for HER3 was performed using formalin-fixed paraffin-embedded surgical specimens and biopsy samples. In total, data from 111 patients with sufficient surgically resected tumor samples were extracted. A total of 28 patients with histology type high-grade serous carcinoma (HGSC) had specimens available from both pre-chemotherapy biopsies and post-chemotherapy surgery. High HER3 expression (HER3-high) was observed in 64 patients (58%), whereas low HER3 expression (HER3-low) was observed in 47 patients (42%). Multivariate logistic regression analysis identified neoadjuvant chemotherapy [odds ratio (OR), 7.49; 95% confidence interval (CI), 2.48-22.64; P<0.001) and non-HGSC histology (OR, 5.42; 95% CI, 1.99-14.78; P<0.001) as significant predictive factors for HER3-high. In pre-chemotherapy biopsy specimens, 15 patients were HER3-high and 13 were HER3-low. After chemotherapy, eight of 13 patients with HER3-low exhibited a change in status to HER3-high, with a trend toward poorer progression-free survival compared to that of patients whose status remained HER3-low. In conclusion, HER3 overexpression was revealed to be common among patients with ovarian cancer, especially in those with non-HGSC histology. In addition, HER3 expression may be promoted by chemotherapy. These findings suggested that patients with ovarian cancer are good candidates for emerging HER3-targeting therapies.

A Comparative Study of Longitudinal Toxicities of Cytotoxic Drugs, Molecularly Targeted Agents, Immunomodulatory Drugs, and Cancer Vaccines.

Little is known about the toxicity of various therapeutics for cancer over time because randomized controlled clinical trials that compare several treatments are limited. In this study, we focused on the toxicities most frequently discussed, which are investigations (lab abnormalities), gastrointestinal disorders, skin and subcutaneous tissue disorders, and cardiac disorders, and compared their longitudinal toxicity data among four types of cancer therapeutics. In total, 28,235 patients who were enrolled into 772 early-phase trials to evaluate the monotherapies of cytotoxic drugs, molecularly targeted agents, immunomodulatory drugs, or cancer vaccines were evaluated. For each toxicity, we compared their grade prevalence, mean grade at each cycle, and time to toxicity occurrence and identified the potential underlying similarities and differences of longitudinal toxicities among the four cancer treatment types. Our results will further help in understanding the profile of cancer therapeutic toxicities and their impact on oncology treatment in practice.