The beneficial effect of probiotics in the prevention of irinotecan-induced diarrhea in colorectal cancer patients with colostomy: a pooled analysis of two probiotic trials (Probio-SK-003 and Probio-SK-005) led by Slovak Cooperative Oncology Group.

Background: Probiotics could decrease irinotecan-induced diarrhea due to the reduction of intestinal beta-d-glucuronidase activity. This study included a combined analysis of two clinical trials aimed to determine the effectiveness of the probiotics in the prophylaxis of irinotecan-induced diarrhea in metastatic colorectal cancer (CRC) patients. Methods: This combined analysis included 46 patients with CRC enrolled in the Probio-SK-003 (NCT01410955) and 233 patients from Probio-SK-005 (NCT02819960) starting a new line of irinotecan-based therapy with identical eligibility criteria. Patients were randomized in a ratio 1:1 to probiotic formulas vs. placebo administered for 12 and 6 weeks, respectively. Due to the different durations of study treatments, only the first 6 weeks of therapy were used for analysis. Results: In total, 279 patients were randomized, including 142 patients in the placebo and 137 participants in the probiotic arm. Administration of probiotics did not significantly reduce the incidence of grade 3/4 diarrhea compared to placebo (placebo 12.7% vs. probiotics 6.6%, p = 0.11). Neither the overall incidence of diarrhea (placebo 48.6% vs. probiotics 41.6%, p = 0.28) nor the incidence of enterocolitis (placebo 4.2% vs. probiotics 0.7%, p = 0.12) was different in the placebo vs. probiotic arm. However, subgroup analysis revealed that patients with a colostomy who received a placebo had a significantly higher incidence of any diarrhea (placebo 51.2% vs. probiotics 25.7%, p = 0.028) and grade 3/4 diarrhea (placebo 14.6% vs. probiotics 0.0%, p = 0.03) compared to the probiotic arm. Conclusions: This combined analysis suggests that probiotics could be beneficial in the prevention of irinotecan-induced diarrhea in colorectal cancer patients with colostomy.

Antibody-drug conjugates as a novel therapeutic modality to treat recurrent refractory germ cell tumors.

This review provides a rationale for using the Food and Drug Administration (FDA)-approved antibody-drug conjugates (ADCs) for implementing as therapy in recurrent refractory germ cell tumors similar to their position in the treatment of other types of chemoresistant solid tumors. Germ cell tumors (GCTs) originate from germ cells; they most frequently develop in ovaries or in the testes, while being the most common type of malignancy in young men. GCTs are very sensitive to cisplatin-based chemotherapy, but therapeutic resistance occurs in a considerable number of cases, which is associated with disease recurrence and poor patient prognosis. ADCs are a novel type of targeted antitumor agents that combine tumor antigen-specific monoclonal antibodies with chemically linked chemotherapeutic drugs (payload) exerting a cytotoxic effect. Several FDA-approved ADCs use as targeting moieties the antigens that are also detected in the GCTs, offering a benefit of this type of targeted therapy even for patients with relapsed/refractory testicular GCTs (rrTGCT) unresponsive to standard chemotherapy.

Epigenetic deregulation in breast cancer microenvironment: Implications for tumor progression and therapeutic strategies.

Breast cancer comprises a substantial proportion of cancer diagnoses in women and is a primary cause of cancer-related mortality. While hormone-responsive cases generally have a favorable prognosis, the aggressive nature of triple-negative breast cancer presents challenges, with intrinsic resistance to established treatments being a persistent issue. The complexity intensifies with the emergence of acquired resistance, further complicating the management of breast cancer. Epigenetic changes, encompassing DNA methylation, histone and RNA modifications, and non-coding RNAs, are acknowledged as crucial contributors to the heterogeneity of breast cancer. The unique epigenetic landscape harbored by each cellular component within the tumor microenvironment (TME) adds great diversity to the intricate regulations which influence therapeutic responses. The TME, a sophisticated ecosystem of cellular and non-cellular elements interacting with tumor cells, establishes an immunosuppressive microenvironment and fuels processes such as tumor growth, angiogenesis, and extracellular matrix remodeling. These factors contribute to challenging conditions in cancer treatment by fostering a hypoxic environment, inducing metabolic stress, and creating physical barriers to drug delivery. This article delves into the complex connections between breast cancer treatment response, underlying epigenetic changes, and vital interactions within the TME. To restore sensitivity to treatment, it emphasizes the need for combination therapies considering epigenetic changes specific to individual members of the TME. Recognizing the pivotal role of epigenetics in drug resistance and comprehending the specificities of breast TME is essential for devising more effective therapeutic strategies. The development of reliable biomarkers for patient stratification will facilitate tailored and precise treatment approaches.

DNA damage levels in peripheral blood mononuclear cells before and after first cycle of chemotherapy have comparable prognostic values in germ cell tumor patients.

Background: Germ cell tumors (GCTs) represent the most frequent solid malignancy in young men. This malignancy is highly curable by cisplatin (CDDP)-based chemotherapy. However, there is a proportion of patients having a poor prognosis due to refractory disease or its relapse. No reliable biomarkers being able to timely and accurately stratify poor prognosis GCT patients are currently available. Previously, we have shown that chemotherapy-naïve GCT patients with higher DNA damage levels in peripheral blood mononuclear cells (PBMCs) have significantly worse prognosis compared to patients with lower DNA damage levels. Methods: DNA damage levels in PBMCs of both chemotherapy-naïve and first cycle chemotherapy-treated GCT patients have been assessed by standard alkaline comet assay and its styrene oxide (SO)-modified version. These levels were correlated with clinico-pathological characteristics. Results: We re-confirm prognostic value of DNA damage level in chemotherapy-naïve GCT patients and reveal that this prognosticator is equally effective in GCT patients after first cycle of CDDP-based chemotherapy. Furthermore, we demonstrate that SO-modified comet assay is comparably sensitive as standard alkaline comet assay in case of patients who underwent first cycle of CDDP-based chemotherapy, although it appears more suitable to detect DNA cross-links. Conclusion: We propose that DNA damage levels in PBMCs before and after first cycle of CCDP-based chemotherapy are comparable independent prognosticators for progression-free and overall survivals in GCT patients. Therefore, their clinical use is highly advised to stratify GCT patients to identify those who are most at risk of developing disease recurrence or relapse, allowing tailoring therapeutic interventions to poor prognosis individuals, and optimizing their care management and treatment regimen.

Chemotherapy-Induced Peripheral Neuropathy (CIPN) as a Predictor of Decreased Quality of Life in Testicular Germ Cell Tumor Survivors.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) after curative treatment for testicular germ cell tumors (GCTs) has been previously reported. It has been shown that CIPN can contribute to impaired quality of life (QOL) in cancer survivors. Herein, we aimed to evaluate CIPN in association with QOL in GCT survivors. PATIENTS AND METHODS: European Organization for Research and Treatment of Cancer (EORTC) Quality of Life - Chemotherapy-Induced Peripheral Neuropathy questionnaire (QLQ-CIPN20) and Quality of Life Questionnaire (QLQ-C30) were prospectively completed by GCT survivors (N = 151) at National Cancer Institute in Slovakia during their annual follow-up. The median follow-up was 10 years (range 4-30). Upon obtaining the scores from each questionnaire, each score from QLQ-C30 was correlated with CIPN defined as high or low (above and below median) as obtained from CIPN20. RESULTS: GCT survivors with high overall CIPN score reported impaired QOL in QLQ-C30. The global health status was lower in survivors with high CIPN versus low CIPN (mean score ± SEM: 67.17 ± 2.00 vs. 86.18 ± 1.76, P < .00001). Survivors with high CIPN reported worse physical, role, emotional, cognitive, and social functioning compared to survivors with low CIPN (all P < .00001). CIPN high survivors perceived more fatigue, nausea, pain, dyspnea, sleeping disorders, and appetite loss compared to CIPN low survivors (all P < .004). Higher burden of CIPN was associated with more financial problems vs CIPN low (mean score ± SEM: 19.70 ± 2.64 vs. 6.67 ± 2.32, P = .00025). Spearman analysis has confirmed negative correlation of overall CIPN20 score with QLQ-C30 global health status (R = -0.53, P < .0001). CONCLUSION: CIPN is a strong predictor of impairment in QOL among GCT survivors. Molecular mechanisms of neurotoxicity should be intensively studied to find preventive and therapeutic strategies.

Exploring the Role of the Gut and Intratumoral Microbiomes in Tumor Progression and Metastasis.

Cancer cell dissemination involves invasion, migration, resistance to stressors in the circulation, extravasation, colonization, and other functions responsible for macroscopic metastases. By enhancing invasiveness, motility, and intravasation, the epithelial-to-mesenchymal transition (EMT) process promotes the generation of circulating tumor cells and their collective migration. Preclinical and clinical studies have documented intensive crosstalk between the gut microbiome, host organism, and immune system. According to the findings, polymorphic microbes might play diverse roles in tumorigenesis, cancer progression, and therapy response. Microbial imbalances and changes in the levels of bacterial metabolites and toxins promote cancer progression via EMT and angiogenesis. In contrast, a favorable microbial composition, together with microbiota-derived metabolites, such as short-chain fatty acids (SCFAs), can attenuate the processes of tumor initiation, disease progression, and the formation of distant metastases. In this review, we highlight the role of the intratumoral and gut microbiomes in cancer cell invasion, migration, and metastatic ability and outline the potential options for microbiota modulation. As shown in murine models, probiotics inhibited tumor development, reduced tumor volume, and suppressed angiogenesis and metastasis. Moreover, modulation of an unfavorable microbiome might improve efficacy and reduce treatment-related toxicities, bringing clinical benefit to patients with metastatic cancer.

Microbiome in Cancer Development and Treatment.

Targeting the microbiome, microbiota-derived metabolites, and related pathways represents a significant challenge in oncology. Microbiome analyses have confirmed the negative impact of cancer treatment on gut homeostasis, resulting in acute dysbiosis and severe complications, including massive inflammatory immune response, mucosal barrier disruption, and bacterial translocation across the gut epithelium. Moreover, recent studies revealed the relationship between an imbalance in the gut microbiome and treatment-related toxicity. In this review, we provide current insights into the role of the microbiome in tumor development and the impact of gut and tumor microbiomes on chemo- and immunotherapy efficacy, as well as treatment-induced late effects, including cognitive impairment and cardiotoxicity. As discussed, microbiota modulation via probiotic supplementation and fecal microbiota transplantation represents a new trend in cancer patient care, aiming to increase bacterial diversity, alleviate acute and long-term treatment-induced toxicity, and improve the response to various treatment modalities. However, a more detailed understanding of the complex relationship between the microbiome and host can significantly contribute to integrating a microbiome-based approach into clinical practice. Determination of causal correlations might lead to the identification of clinically relevant diagnostic and prognostic microbial biomarkers. Notably, restoration of intestinal homeostasis could contribute to optimizing treatment efficacy and improving cancer patient outcomes.