DNA Damage Repair Defects and Targeted Radionuclide Therapies for Prostate Cancer: Does Mutation Really Matter? A Systematic Review

Future Treatment Strategies for Cancer Patients Combining Targeted Alpha Therapy with Pillars of Cancer Treatment: External Beam Radiation Therapy, Checkpoint Inhibition Immunotherapy, Cytostatic Chemotherapy, and Brachytherapy

Cancer is one of the most complex and challenging human diseases, with rising incidences and cancer-related deaths despite improved diagnosis and personalized treatment options. Targeted alpha therapy (TαT) offers an exciting strategy emerging for cancer treatment which has proven effective even in patients with advanced metastatic disease that has become resistant to other treatments. Yet, in many cases, more sophisticated strategies are needed to stall disease progression and overcome resistance to TαT. The combination of two or more therapies which have historically been used as stand-alone treatments is an approach that has been pursued in recent years. This review aims to provide an overview on TαT and the four main pillars of therapeutic strategies in cancer management, namely external beam radiation therapy (EBRT), immunotherapy with checkpoint inhibitors (ICI), cytostatic chemotherapy (CCT), and brachytherapy (BT), and to discuss their potential use in combination with TαT. A brief description of each therapy is followed by a review of known biological aspects and state-of-the-art treatment practices. The emphasis, however, is given to the motivation for combination with TαT as well as the pre-clinical and clinical studies conducted to date.

Design of 225Ac-PSMA for targeted alpha therapy in prostate cancer

The first alpha emitting radiopharmaceutical, 223RaCl2, radium dichloride, was approved 10 years ago into the clinical armament of treating bone metastases in metastatic castration-resistant prostate cancer (mCRPC). In addition to this, the first beta-emitting radionuclide Lu-177 chelated with a prostate-specific membrane antigen (PSMA) compound, got last year its marketing approval for the third line treatment of mCRPC. Therefore, there is great excitement about combining alpha-emitters and prostate cancer targeting PSMA compounds. This review describes the clinical history of alpha-emitting PSMA in treating mCRPC. Here, we present the potential, current status, and opportunities for 225Ac-PSMA therapy. The work reviews the basic concepts, current treatment outcome, and toxicity, and areas requiring further investigations such as dosimetric aspects in clinical studies covering more than 400 patients. In general, approximately two-thirds of the patients benefit from this third-line therapy. There is also successful evidence of using 225Ac-PSMA in the second-line of prostate cancer management. The future potential of 225Ac-PSMA therapy and targeted alpha therapy (TAT) of cancer in general is enormous. According to our overview the clinical experience with 225Ac-PSMA therapy to date has shown great benefit and physicians dedicated to theragnostics are anxiously waiting for new applications. Hopefully, this review helps in deeper understanding of the strengths and limitations of TAT and may help in creating effective therapy protocols.

PSMA-based therapeutics for prostate cancer

INTRODUCTION

The prostate cancer (PCa) consists the most frequently diagnosed malignancy of urogenital system in males. Traditionally, treatment of localized PCa was based on surgery or radiotherapy while hormonotherapy was used in more advanced stages. However, the implementation of radiolabels has revolutionized the landscape of prostate cancer. Specifically, prostate-specific membrane antigen (PSMA) has been investigated in different aspects of PCa therapeutic era.

AREAS COVERED

A literature review is presented about the implications of PSMA radiolabels on prostate cancer treatment. PSMA tracers were initially used as an imaging technique. Afterwards, PSMA labeled with isotopes presenting cytotoxic abilities, such as lutetium-117 and actinium-225, while reports exist about the use of radioligand immunotherapy. Meanwhile, ongoing trials examine the development of novel radionuclides as well as the evolution of the PSMA-targeted ligands.

EXPERT OPINION

Currently, PSMA radioligand treatment of prostate cancer is approved in the metastatic stage of the disease. Meanwhile, a variety of trials exist about its possible role in less advanced stages. However, plenty of parameters should be addressed before these implementations, such as PSMA dosage, dosimetry issues, and its safety profile. A future well-designed study with proper patient selection is mandatory to further explore PSMA radioligand theranostics perspectives.

The application of radionuclide therapy for breast cancer

Radionuclide-mediated diagnosis and therapy have emerged as effective and low-risk approaches to treating breast cancer. Compared to traditional anatomic imaging techniques, diagnostic radionuclide-based molecular imaging systems exhibit much greater sensitivity and ability to precisely illustrate the biodistribution and metabolic processes from a functional perspective in breast cancer; this transitions diagnosis from an invasive visualization to a noninvasive visualization, potentially ensuring earlier diagnosis and on-time treatment. Radionuclide therapy is a newly developed modality for the treatment of breast cancer in which radionuclides are delivered to tumors and/or tumor-associated targets either directly or using delivery vehicles. Radionuclide therapy has been proven to be eminently effective and to exhibit low toxicity when eliminating both primary tumors and metastases and even undetected tumors. In addition, the specific interaction between the surface modules of the delivery vehicles and the targets on the surface of tumor cells enables radionuclide targeting therapy, and this represents an exceptional potential for this treatment in breast cancer. This article reviews the development of radionuclide molecular imaging techniques that are currently employed for early breast cancer diagnosis and both the progress and challenges of radionuclide therapy employed in breast cancer treatment.

Development and validation of a DNA damage repair-related gene-based prediction model for the prognosis of lung adenocarcinoma

Background

Lung cancer is the leading cause of morbidity and mortality among all cancer types, with lung adenocarcinoma (LUAD) being the most prevalent subtype. DNA damage repair (DDR)-related genes are closely associated with cancer progression and treatment, with emerging evidence highlighting their correlation with tumor development. However, the relationship between LUAD prognosis and DDR-related genes remains unclear.

Methods

RNA sequencing (RNA-seq) data and clinical information were obtained from The Cancer Genome Atlas (TCGA) database. The GSE31210 dataset, utilized for external validation, was retrieved from the Gene Expression Omnibus (GEO) database. Differentially expressed DDR genes were identified, and a DDR-related prognostic model was established and validated using Kaplan-Meier (KM) survival analysis, time-dependent receiver operating characteristic (ROC) curves, gene set enrichment analysis (GSEA), tumor mutational burden (TMB) analysis, and immune cell infiltration. A P value of less than 0.05 was considered statistically significant.

Results

A total of 514 patients with LUAD from TCGA database were divided into distinct subtypes to characterize the diversity within the DDR pathway. DDR-activated and DDR-suppressed subgroups showed distinct clinical characteristics, molecular characteristics, and immune profiles. Nine genes were identified as hub DDR-related genes, including CASP14, DKK1, ECT2, FLNC, HMMR, IGFBP1, KRT6A, TYMS, and FCER2. By using the expression levels of these selected genes, the corresponding risk scores for each sample was predicted. In the training group, KM survival analysis revealed that the high-risk group exhibited significantly diminished overall survival (OS) [hazard ratio (HR) =3.341, P=1.38e-08]. The corresponding area under the curve (AUC) values for the 1-year follow-up periods was 0.767, respectively. Upon validation in the external cohort, patients with higher risk scores manifested significantly reduced OS (HR =2.372, P=1.87e-03). The AUC values of the ROC curves for the 1-year OS in the validation cohort was 0.87, respectively. Moreover, advanced DDR risk score was correlated with increased TMB scores, a heightened frequency of TP53 mutations, an increased abundance of cancer-testicular antigens (CTAs), and a lower tumor immune dysfunction and exclusion (TIDE) score in patients with LUAD (P<0.05).

Conclusions

A nine-gene risk signature associated with DDR in LUAD was effectively developed, demonstrating its potential as a robust and reliable classification tool for clinical practice. This model exhibited the capability to accurately predict the prognosis and survival outcomes of LUAD patients.

Molecular imaging of PARP in cancer: state-of-the-art

INTRODUCTION

Poly-ADP-ribose-polymerase inhibitors (PARPi), which exploit the processes of so-called 'synthetic lethality,' have been successfully implemented in oncological practice. However, not all patients respond to PARPi, and there is an unmet need for noninvasive biomarkers suitable for patient selection and monitoring during PARPi therapy.

AREAS COVERED

The first clinical applications of molecular imaging with positron emission tomography/computed tomography (PET/CT) with [18F]-FluorThanatrace ([18F]-FTT) and [18F]-PARPi, highly effective PARP-ligands, in patients with several malignancies (head and neck, ovarian, prostate, and breast cancer) are covered, with a particular focus on its potential for pre-treatment selection and follow-up.

EXPERT OPINION

By a search made on the most common database, such as PubMed and Google Scholar in a period from January 2010 and 2023, first clinical evidence suggests that PET/CT with [18F]-FTT and [18F]-PARPi might represent a reliable tool for in vivo imaging and quantification of PARP-1 expression in ovarian, prostate, breast, head, and neck cancer, supporting their potential usefulness for patient selection before PARPi-therapies. In addition, a reduction in [18F]-FTT uptake has been registered after therapy initiation and seems to be correlated with patient outcome after PARPi-based regimens. Further studies are needed to better address the value of PARPI-radiolabeled PET imaging in these clinical settings, especially as it concerns technical features such as optimal scan modality (dynamic vs. static) and timing.

Efficacy and adverse reaction management of oncolytic viral intervention combined with chemotherapy in patients with liver metastasis of gastrointestinal malignancy

Background

The liver is a key target organ for colorectal and gastric cancer metastasis. One of the challenges in the treatment of colorectal and gastric cancers is the management of liver metastasis. This study aimed to investigate the efficacy, adverse effects, and coping strategies of oncolytic virus injection in patients with liver metastases of gastrointestinal malignancies.

Methods

We prospectively analyzed patients treated at Ruijin Hospital affiliated with Shanghai Jiao Tong University School of Medicine from June 2021 to October 2022. 47 patients with gastrointestinal cancer liver metastasis were included in the study. The data, including clinical manifestations, imaging, tumor markers, postoperative adverse reactions, psychological intervention, dietary guidance, and adverse reaction management were evaluated.

Results

Oncolytic virus injection was successful in all patients, and no drug injection-related deaths occurred. The adverse effects, such as fever, pain, bone marrow suppression, nausea, and vomiting, were mild and resolved subsequently. Based on the comprehensive intervention of nursing procedures, the postoperative adverse reactions of patients were effectively alleviated and treated. None of the 47 patients had any puncture point infections, and the pain caused by the invasive operation was relieved quickly. After 2 courses of oncolytic virus injection, postoperative liver MRI showed 5 partial remissions, 30 stable diseases, and 12 progressive diseases in target organs.

Conclusion

Interventions based on nursing procedures can ensure the smooth treatment of recombinant human adenovirus type 5 in patients with liver metastases of gastrointestinal malignant tumors. This is of great importance for clinical treatment and significantly reduces patient complications and improves the patient's quality of life.