Biomedical Journal

Significant decrease of a master regulator of genes (REST/NRSF) in high-grade squamous intraepithelial lesion and cervical cancer

The repressor element 1-silencing transcription factor (REST) is a regulator of gene expression, and the Ras association domain family member 1 A (RASSF1A) is an important tumor suppressor gene involved in cancer development. Although extensive characterization of the roles of REST and RASSF1A in cancer development have been reported in cellular models, the link between them and their possible role in the development of squamous intraepithelial lesions (SIL) and squamous cell carcinoma (SCC) of the cervix have not been explored. The aim of this study was to evaluate the expression of REST and RASSF1A in cervical cytological and histological samples from patients diagnosed with SIL or SCC and in CC-derived cell lines. We analyzed the expression of REST and RASSF1A by immunocyto/histochemistry in cervical samples from patients (n = 271) and in cancer cell lines. Data analyses were performed using the Kruskal-Wallis test and generalized linear models. We identified binding sites for REST in RASSF1A and observed a significant reduction in REST and RASSF1A nuclear expression in samples from patients with high-grade SIL (HSIL) and SCC. For REST, we observed an average decrease of 334 and 423 r.u.d. for HSIL (n = 21) and SCC (n = 18) compared with non-LSIL (n = 72), whereas for RASSF1A, this decrease was 126 and 217 r.u.d., respectively (p < 0.001). Our results provide evidence of the altered expression of REST and RASSF1A in SIL and SCC, with a significant decrease in HSIL, SCC, and SCC-derived cell lines; findings that can contribute to the diagnosis, prognosis, and post-treatment follow-up of patients diagnosed with SIL or SCC.

Small cell neuroendocrine carcinoma of the cervix: From molecular basis to therapeutic advances

Small cell neuroendocrine carcinoma of the cervix (SCNECC) is an uncommon but aggressive uterine malignancy, the cause of which is generally associated with human papillomavirus (HPV) infection. A lack of clinical trials and evidence-based treatment guidelines poses therapeutic challenges to this rare tumor. At present, published data remain limited to case series and case reports. While clinical management has traditionally followed those of small cell neuroendocrine (SCNE) lung cancer relying on surgery, chemoradiation, and systemic chemotherapy, the prognosis remains dismal. Immune checkpoint inhibitors (ICIs), such as monoclonal antibodies that target programmed death-1 (PD-1) or programmed death-ligand 1 (PD-L1), atezolizumab and durvalumab have proven effective in extensive-stage SCNE lung cancer. Moreover, pembrolizumab has also proven beneficial effects when added onto chemotherapy in metastatic and recurrent HPV-associated non-SCNE cervical cancer. It holds promise to use ICIs in combination with chemoradiation to improve the clinical outcomes of patients with SCNECC. Future advances in our understanding of SCNECC biology - associated with the study of its genomic and molecular aberrations as well as knowledge from SCNE of lung and other extrapulmonary sites- would be helpful in discovering new molecular targets for drug development. Collaborative efforts and establishment of a SCNECC-specific biobank will be essential to achieve this goal.

Mutations in circulating tumor DNA detected in the postoperative period predict poor survival in patients with ovarian cancer

We investigated whether mutations in plasma circulating tumor DNA (ctDNA) can provide prognostic insight in patients with different histological types of ovarian carcinoma. We also examined the concordance of mutations detected in ctDNA samples with those identified in the corresponding formalin-fixed paraffin-embedded (FFPE) tumor specimens. Between July 2016 and December 2017, 29 patients with ovarian carcinoma were prospectively enrolled. FFPE tumor specimens were obtained from all participants. A total of 187 blood samples for ctDNA analysis were collected before surgery (C0), immediate after surgery before adjuvant chemotherapy (C1), and at six-month intervals. Progression-free survival (PFS) and overall survival (OS) served as the main outcome measures. The study cohort consisted of 13 (44.8%) patients with high-grade serous carcinomas (HGSC), 9 (31.0%) with clear cell carcinoma, 2 (6.9%) with mucinous carcinomas, 4 (13.8%) with low-grade serous carcinomas, and 1 (3.4%) with endometrioid carcinoma. Twenty-four (82.8%) patients had at least one detectable ctDNA variant. The concordance rate between mutations identified in pretreatment ctDNA and corresponding FFPE tumor specimens was 92.3% for patients with HGSC and 58.6% for the entire cohort. The median follow-up time was 33.15 months (range: 0.79-46.13 months). Patients with an advanced stage disease more likely had detectable ctDNA mutations before surgery (C0) and after surgery at C1, while those with HGSC more likely had ctDNA mutations detected before surgery. The presence of ctDNA mutations at C1 was an independent predictor of worse OS with a hazard ratio of 6.56 (95% confidence interval, (1.07-40.17) for detectable versus undetectable C1 ctDNA variants, p = 0.042). ctDNA mutations are common in patients with ovarian carcinoma. The presence of ctDNA mutations after surgery was an independent predictor of less favorable PFS and OS.

Hyperthermic intraperitoneal chemotherapy for recurrent epithelial ovarian cancer

To investigate outcomes and morbidity of patients undergoing secondary cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in recurrent ovarian cancer. Between April 2014 and January 2019, a total of 51 recurrent ovarian cancer patients receiving secondary CRS and HIPEC were retrospectively reviewed. Among the 51 patients, median peritoneal cancer index score was 13 (range 3-34), and completeness of cytoreduction (CC) score of 0/1 was achieved in 41 patients (78.8%). Regimen of HIPEC included cisplatin and paclitaxel in 39 (75%) cases. The median follow-up duration of survivors was 20.2 months. Sixteen (30.8%) patients remained free of recurrence after HIPEC. The median progression-free survival (PFS) and overall survival (OS) were 11.8 months and 34.5 months respectively. Multivariate analysis showed previous chemotherapy &lt;2 lines (HR 0.24, 0.11-0.52; p = 0.001), chemotherapy-free interval ≥6 months (HR 0.19, 0.09-0.37; p &lt; 0.001) and CA125 &lt; 35 U/mL before HIPEC (HR 0.133, 0.021-0.0832; p = 0.031) were good prognostic factors for PFS. CC0/1 was not significant in multivariate analysis. The most common grade 3/4 toxicity was anemia (17.3%), pleural effusion (11.5%) and renal insufficiency (5.7%). Patients with age ≥50, peritoneal carcinomatosis index (PCI) ≥ 11, operation time ≥10 h and diaphragm surgery had significantly higher incidence of pleural effusion. The current study showed adding HIPEC to secondary CRS might prolong PFS especially in patients with previous chemotherapy &lt;2 lines, chemotherapy-free interval ≥6 months and CA125 &lt; 35 U/mL before HIPEC.

Mitochondrial dysfunction route as a possible biomarker and therapy target for human cancer

Mitochondria are vital organelles found within living cells and have signalling, biosynthetic, and bioenergetic functions. Mitochondria play a crucial role in metabolic reprogramming, which is a characteristic of cancer cells and allows them to ensure a steady supply of proteins, nucleotides, and lipids to enable rapid proliferation and development. Their dysregulated activities have been associated with the growth and metastasis of different kinds of human cancer, particularly ovarian carcinoma. In this review, we briefly demonstrated the modified mitochondrial function in cancer, including mutations in mitochondrial DNA (mtDNA), reactive oxygen species (ROS) production, dynamics, apoptosis of cells, autophagy, and calcium excess to maintain cancer genesis, progression, and metastasis. Furthermore, the mitochondrial dysfunction pathway for some genomic, proteomic, and metabolomics modifications in ovarian cancer has been studied. Additionally, ovarian cancer has been linked to targeted therapies and biomarkers found through various alteration processes underlying mitochondrial dysfunction, notably targeting (ROS), metabolites, rewind metabolic pathways, and chemo-resistant ovarian carcinoma cells.