Management and clinical outcomes of patients with recurrent/progressive ovarian clear cell carcinoma

Inhibition of nucleophosmin/B23 sensitizes ovarian cancer cells to immune check-point blockade via PD-L1 in ovarian cancer

BACKGROUND

Immune checkpoint inhibitors (ICIs) that against programmed cell death protein-1 (PD-1) and its ligand PD-L1 have been approved as a promising treatment of many human cancers. However, the responses to these ICIs were limited in patients with ovarian cancer. Studies have indicated that the response to PD-1/PD-L1 blockade might be correlated with the PD-L1 expression level in cancer cells. Nucleophosmin (NPM/B23) was found to be a potential target for immunotherapy. Whether NPM/B23 plays a role in cancer-associated immunity, such as PD-1/PD-L1 axis, and its underlying mechanisms remain largely unknown in ovarian cancer.

METHODS

We applied ovarian cancer cell lines as research models. The effect of modulating PD-L1 by NPM/B23 was subsequently confirmed via Western blot, flow cytometry, qRT-PCR, luciferase reporter assays, and immunoprecipitation. Protein stability and ubiquitin assay assays were used to analyze the interplay between NPM/B23 and NF-ĸB/p65 in PD-L1 regulation. The MOSEC/Luc xenograft mouse model was used to validate the role of NPM/B23-PD-L1 through tumor growth in vivo.

RESULTS

Our results revealed that NPM/B23 negatively regulates PD-L1 expression via a protein complex with NF-κB/p65 and through an IFN-γ pathway. Moreover, NPM/B23 inhibitor/modulator sensitized ovarian cancer cells to the anti-PD-1 antibody by regulating PD-L1 expression in the immunocompetent mouse model. Compared to anti-PD-1 antibody alone, a combination of anti-PD-1 antibody and NPM/B23 inhibitor/modulator showed reduced tumorigenesis and increased CD8+ T-cell expansion, thus contributing to prolonged survival on MOSEC/Luc-bearing mouse model.

CONCLUSION

Targeting NPM/B23 is a novel and potential therapeutic approach to sensitize ovarian cancer cells to immunotherapy.

Personalized neoantigen-based T cell therapy triggers cytotoxic lymphocytes expressing polyclonal TCR against metastatic ovarian cancer

Neoantigen-reactive cytotoxic T lymphocytes play a vital role in precise cancer cell elimination. In this study, we demonstrate the effectiveness of personalized neoantigen-based T cell therapy in inducing tumor regression in two patients suffering from heavily-burdened metastatic ovarian cancer. Our approach involved the development of a robust pipeline for ex vivo expansion of neoantigen-reactive T lymphocytes. Neoantigen peptides were designed and synthesized based on the somatic mutations of the tumors and their predicted HLA binding affinities. These peptides were then presented to T lymphocytes through co-culture with neoantigen-loaded dendritic cells for ex vivo expansion. Subsequent to cell therapy, both patients exhibited significant reductions in tumor marker levels and experienced substantial tumor regression. One patient achieved repeated cancer regression through infusions of T cell products generated from newly identified neoantigens. Transcriptomic analyses revealed a remarkable increase in neoantigen-reactive cytotoxic lymphocytes in the peripheral blood of the patients following cell therapy. These cytotoxic T lymphocytes expressed polyclonal T cell receptors (TCR) against neoantigens, along with abundant cytotoxic proteins and pro-inflammatory cytokines. The efficacy of neoantigen targeting was significantly associated with the immunogenicity and TCR polyclonality. Notably, the neoantigen-specific TCR clonotypes persisted in the peripheral blood after cell therapy. Our findings indicate that personalized neoantigen-based T cell therapy triggers cytotoxic lymphocytes expressing polyclonal TCR against ovarian cancer, suggesting its promising potential in cancer immunotherapy.

Role of radiotherapy in the management of rare gynaecological cancers

There are a large number of gynaecological cancers with rare histologies, for which the available data are limited and usually retrospective. Because of their rarity and poor prognosis, the management of these cancers must be centralized in expert centres, for both histological diagnosis and treatment. With the exception of sarcomas, most endometrial or cervical cancers with rare histologies respond to the same radiation treatment modalities than cancers with more common histologies, although there are some specificities regarding treatments such as neuroendocrine carcinomas (chemotherapy with platinum and etoposide, major role of surgery). For localized or locally advanced ovarian cancer, external beam radiotherapy has a role in the management of hypercalcaemic small cell carcinoma of the ovary. This article summarizes the current role of external beam radiotherapy and brachytherapy in the management of cancers of the uterine cervix, uterine corpus and ovaries, with rare or very rare histologies, and with localized or locally advanced stages.

Multi-stage optimal dynamic treatment regimes for survival outcomes with dependent censoring

We propose a reinforcement learning method for estimating an optimal dynamic treatment regime for survival outcomes with dependent censoring. The estimator allows the failure time to be conditionally independent of censoring and dependent on the treatment decision times, supports a flexible number of treatment arms and treatment stages, and can maximize either the mean survival time or the survival probability at a certain time-point. The estimator is constructed using generalized random survival forests and can have polynomial rates of convergence. Simulations and analysis of the Atherosclerosis Risk in Communities study data suggest that the new estimator brings higher expected outcomes than existing methods in various settings.

The Significance of Radiotherapy in Ovarian Clear Cell Carcinoma: A Systematic Review and Meta-Analysis

OBJECTIVE

To assess the response rate and survival effect of adjuvant radiotherapy (RT) or chemoradiotherapy (CRT) during ovarian clear cell carcinoma (OCCC).

METHODS

We searched Web of Science, PubMed, Cochrane library electronic databases, Clinical Trials, WanFang Data and Chinese National Knowledge Infrastructure (CNKI) up to October 2022. We also searched registers of clinical trials, abstracts of scientific meetings and reference lists of included studies.

RESULTS

We identified a total of 4259 patients from 14 studies met the inclusion criteria. The pooled response rate of residual tumors for RT/CRT was 80.0%, the pooled 5-year progression-free survival (PFS) ratio during RT/CRT group was 61.0%, and the pooled 5-year overall survival (OS) ratio during RT/CRT group was 68.0%; heterogeneity tests demonstrated significant difference between studies (I² >50%). Cumulative results suggested adjuvant RT/CRT improved 5-year PFS ratio of OCCC patients (OR: 0.51 (95% CI: 0.42-.88), I² = 22%, P = .009), had no impact on 5-year OS ratio (OR: 0.52 (95% CI: 0.19-1.44), I² = 87%, P = .21); meta-regression of studies before and after 2000 found consistent results. Sub-analysis observed that adjuvant RT/CRT had no impact on 5-year OS ratio of early-stage (stage I + II) OCCC patients (OR: 0.67 (95% CI: 0.25-1.83), I² = 85%, P = .44), but might improve 5-year OS ratio of advanced and recurrent OCCC patients (OR: 0.13(95% CI: 0.04-.44), P = .001).

CONCLUSION

This analysis suggested that adjuvant RT/CRT might improve oncologic outcomes of OCCC, especially for advanced and recurrent cases. Due to the inherent selective biases of retrospective studies enrolled in the meta-analysis, more convincing evidences based on prospective randomized controlled trials (RCTs) are urgently needed.

Incidence and predictive factors for recurrent clear cell ovarian carcinoma: results from a single center in Thailand

Objective

We aimed to study the incidence and predictive factors of recurrent clear cell ovarian carcinoma (CCC) and evaluate the oncological outcomes after recurrence.

Methods

This was a retrospective study of 134 CCC cases diagnosed between 2005 and 2020. Clinicopathological data and oncological outcomes were extracted and evaluated. Patients with co-malignancy, mixed pathological type, or incomplete data were excluded. Descriptive statistics, univariate and multivariable analyses, and Kaplan-Meier survival probability estimates were completed. A proportional hazards model was used to assess the association between the prognostic factors with progression-free survival (PFS), overall survival (OS), and post-recurrence survival.

Results

A total of 134 patients with CCC were enrolled. The incidence of recurrent CCC was 33.6% (45/134). The median PFS was 12.8 months (95% confidence interval [CI], 9.66–18.9) in the recurrence group and 3.3 months (95% CI, 1.15–4.4) in the refractory group. Residual tumor from surgical outcome, ascites cytology, and lymphovascular space invasion (LVSI) were independent prognostic factors for PFS. The significant variables were residual tumor (sub-optimal surgery vs. optimal surgery) (hazard ratio [HR], 2.68; 95% CI, 1.48–4.87; P=0.002), ascites cytology (positive vs. negative) (HR, 2.8; 95% CI, 1.58–4.98; P=0.002), and LVSI (positive vs. negative) (HR, 2.14; 95% CI, 1.18–3.86; P=0.04). The median post-recurrence survival was 13.96 months (95% CI, 10.61–26.2) in the recurrence group.

Conclusion

CCC has a high rate of recurrence. Sub-optimal surgery, positive ascites cytology, and LVSI indicated a worse prognosis for PFS. Optimal cytoreductive surgery is an important part of primary treatment to improve survival in patients with CCC.

Serum levels of alpha1-antitrypsin isoforms in patients with ovarian clear cell carcinoma: An exploratory study

BACKGROUND

Ovarian clear cell carcinoma (OCCC) is frequently associated with endometriosis. Since serum levels of cancer antigen 125 (CA125) have limited diagnostic and prognostic value in this malignancy, there is an unmet need for reliable and specific biomarkers. Previous findings indicated that alpha 1-antitrypsin isoforms (isoAAT) are significantly increased in the peritoneal fluid of patients with endometriosis. This study was undertaken to examine whether serum isoAAT levels in patients with OCCC differ from those measured in women with endometriosis or benign ovarian tumors. We also investigated whether this biomarker may be useful for predicting survival in OCCC.

METHODS

Paired serum samples before and after debulking surgery were collected from 27 patients with OCCC. All sera from patients with endometriosis (n = 44) and benign ovarian tumors (n = 32) were obtained in the pretreatment phase. Serum isoAAT levels were assayed using a proprietary ELISA kit.

RESULTS

The highest levels of serum isoAAT (median, range) were identified in patients with OCCC (preoperative values: 160.9 ng/mL, range, 101.4-1098.8 ng/mL), followed by patients with endometriosis (125.0 and 83.4-473.2 ng/mL), and those with benign tumors (125.2 and 60.5-191.3 ng/mL). The differences in serum isoAAT levels between patients with OCCC and benign tumors were significant (p = 0.041). Debulking surgery of OCCC resulted in a significant decrease in serum isoAAT levels compared with the preoperative period (median, 160.9 versus 113.0 ng/mL, respectively, p = 0.012). As for prognostic prediction, we found that none of the nine patients with OCCC and serum isoAAT levels ≤130 ng/mL died of disease.

CONCLUSION

Serum isoAAT levels may be diagnostically useful to distinguish OCCC from benign ovarian tumors and could also serve as a potential prognostic marker.

Detection and prognostic significance of isolated tumor cells and micrometastases in pelvic lymph nodes of patients with early ovarian clear cell carcinoma

BACKGROUND/PURPOSE

Ovarian clear cell carcinoma (OCCC) accounts for approximately 18% of all epithelial ovarian malignancies in Taiwan and portends a poor prognosis. Here, we sought to investigate whether immunohistochemistry with an anti-pan-cytokeratin antibody cocktail (AE1/AE3) can be used as an adjunct to hematoxylin and eosin (H&E) staining for improving the detection of isolated tumor cells (ITCs) and micrometastasis to pelvic lymph nodes (LNs). We also assessed whether these lesions may predict disease recurrence.

METHODS

Pelvic lymphadenectomy specimens were obtained from 197 patients with stage 1 OCCC who had undergone surgery between 2000 and 2018 from Linkou and Kaohsiung Chang Gung Memorial Hospital. Immunohistochemical staining with AE1/AE3 was applied to a total of 1186 slides. Clusters of metastatic tumor cells, detected immunohistochemically, were classified as ITCs (clusters with diameters of ≤0.2 mm) or micrometastases (tumor cell clusters of >0.2 but ≤2.0 mm). We also assessed the diameter of metastases in patients with positive lymph nodes (stage IIIA1, n = 3, 7 positive nodes).

RESULTS

Clusters with a positive AE1/AE3 staining were identified in five (2.53%) of the 197 patients (ITCs, n = 3; micrometastasis, n = 2). Four patients had no evidence of disease recurrence but a patient recurred at follow-up. Metastatic foci of patients with stage IIIA1 disease were all >2.0 mm in size.

CONCLUSION

Immunohistochemical staining with AE1/AE3 can identify micrometastasis or ITCs in LNs missed on routine H&E staining. The role of micrometastasis in predicting recurrent OCCC and implementing on treatment strategies requires further investigation.