Platinum rechallenge treatment using gemcitabine plus carboplatin with or without bevacizumab for platinum-resistant ovarian cancer

Epigenetics as a strategic intervention for early diagnosis and combatting glycolyis-induced chemoresistance in gynecologic cancers

Prospective prediction from the Australian Institute of Health and Welfare (AIHW) showed a likely incidence of 1 in 23 women diagnosed with gynaecological malignancy, where the incidence of relapse with a drug-resistant clone poses a significant challenge in dealing with it even after initial treatment. Glucose metabolism has been exploited as a therapeutic target under anti-metabolomic study, but the non-specificity narrowed its applicability in cancer. Novel updates over epigenetics as a target in gynaecological cancer offer a rational idea of using this in the metabolic rewiring in mutated glycolytic flux-induced drug resistance. This review focuses on the application of epigenetic intervention at a diagnostic and therapeutic level to shift the current treatment paradigm of gynaecological cancers from reactive medicine to predictive, preventive, and personalised medicine. It presents the likely epigenetic targets that can be exploited potentially to prevent the therapeutic failure associated with glucose metabolism-induced chemotherapeutic drug resistance.

Co-targeting CDK 4/6 and C-MYC/STAT3/CCND1 axis and inhibition of tumorigenesis and epithelial-mesenchymal-transition in triple negative breast cancer by Pt(II) complexes bearing NH3 as trans-co-ligand

In search of potential anticancer agents, we synthesized SNO-donor salicylaldimine main ligand-based Pt(II) complexes bearing NH3 as co-ligand at trans-position (C1-C6). These complexes showed similarity in structure with transplatin as the two N donor atoms of the main ligand and NH3 co-ligand were coordinated to Pt in trans position to each other. Each complex with different substituents on the main ligand was characterized thoroughly by detailed spectroscopic and spectrophotometric methods. Four of these complexes were studied in solid state by single crystal X-ray analysis. The stability of reference complex C1 was measured in solution state in DMSO‑d6 or its mixture with D2O using 1H NMR methods. These complexes were further investigated for their anticancer activity in triple-negative-breast (TNBC) cells including MDA-MB-231, MDA-MB-468 and MDA-MB-436 cells. All these complexes showed satisfactory cytotoxic effect as revealed by the MTT results. Importantly, the highly active complex C4 anticancer effect was compared to the standard chemotherapeutic agents including cisplatin, oxaliplatin and 5-fluorouracil (5-FU). Functionally, C4 suppressed invasion, spheroids formation ability and clonogenic potential of cancer cells. C4 showed synergistic anticancer effect when used in combination with palbociclib, JQ1 and paclitaxel in TNBC cells. Mechanistically, C4 inhibited cyclin-dependent kinase (CDK)4/6 pathway and targeted the expressions of MYC/STAT3/CCND1/CNNE1 axis. Furthermore, C4 suppressed the EMT signaling pathway that suggested a role of C4 in the inhibition of TNBC metastasis. Our findings may pave further in detailed mechanistic study on these complexes as potential chemotherapeutic agents in different types of human cancers.

Angiogenesis inhibitors for the treatment of epithelial ovarian cancer

BACKGROUND

Many women, and other females, with epithelial ovarian cancer (EOC) develop resistance to conventional chemotherapy drugs. Drugs that inhibit angiogenesis (development of new blood vessels), essential for tumour growth, control cancer growth by denying blood supply to tumour nodules.

OBJECTIVES

To compare the effectiveness and toxicities of angiogenesis inhibitors for treatment of epithelial ovarian cancer (EOC).

SEARCH METHODS

We identified randomised controlled trials (RCTs) by searching CENTRAL, MEDLINE and Embase (from 1990 to 30 September 2022). We searched clinical trials registers and contacted investigators of completed and ongoing trials for further information.

SELECTION CRITERIA

RCTs comparing angiogenesis inhibitors with standard chemotherapy, other types of anti-cancer treatment, other angiogenesis inhibitors with or without other treatments, or placebo/no treatment in a maintenance setting, in women with EOC.  DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. Our outcomes were overall survival (OS), progression-free survival (PFS), quality of life (QoL), adverse events (grade 3 and above) and hypertension (grade 2 and above).

MAIN RESULTS

We identified 50 studies (14,836 participants) for inclusion (including five studies from the previous version of this review): 13 solely in females with newly-diagnosed EOC and 37 in females with recurrent EOC (nine studies in platinum-sensitive EOC; 19 in platinum-resistant EOC; nine with studies with mixed or unclear platinum sensitivity). The main results are presented below.  Newly-diagnosed EOC Bevacizumab, a monoclonal antibody that binds vascular endothelial growth factor (VEGF), given with chemotherapy and continued as maintenance, likely results in little to no difference in OS compared to chemotherapy alone (hazard ratio (HR) 0.97, 95% confidence interval (CI) 0.88 to 1.07; 2 studies, 2776 participants; moderate-certainty evidence). Evidence is very uncertain for PFS (HR 0.82, 95% CI 0.64 to 1.05; 2 studies, 2746 participants; very low-certainty evidence), although the combination results in a slight reduction in global QoL (mean difference (MD) -6.4, 95% CI -8.86 to -3.94; 1 study, 890 participants; high-certainty evidence). The combination likely increases any adverse event (grade ≥ 3) (risk ratio (RR) 1.16, 95% CI 1.07 to 1.26; 1 study, 1485 participants; moderate-certainty evidence) and may result in a large increase in hypertension (grade ≥ 2) (RR 4.27, 95% CI 3.25 to 5.60; 2 studies, 2707 participants; low-certainty evidence). Tyrosine kinase inhibitors (TKIs) to block VEGF receptors (VEGF-R), given with chemotherapy and continued as maintenance, likely result in little to no difference in OS (HR 0.99, 95% CI 0.84 to 1.17; 2 studies, 1451 participants; moderate-certainty evidence) and likely increase PFS slightly (HR 0.88, 95% CI 0.77 to 1.00; 2 studies, 2466 participants; moderate-certainty evidence). The combination likely reduces QoL slightly (MD -1.86, 95% CI -3.46 to -0.26; 1 study, 1340 participants; moderate-certainty evidence), but it increases any adverse event (grade ≥ 3) slightly (RR 1.31, 95% CI 1.11 to 1.55; 1 study, 188 participants; moderate-certainty evidence) and may result in a large increase in hypertension (grade ≥ 3) (RR 6.49, 95% CI 2.02 to 20.87; 1 study, 1352 participants; low-certainty evidence).  Recurrent EOC (platinum-sensitive) Moderate-certainty evidence from three studies (with 1564 participants) indicates that bevacizumab with chemotherapy, and continued as maintenance, likely results in little to no difference in OS (HR 0.90, 95% CI 0.79 to 1.02), but likely improves PFS (HR 0.56, 95% CI 0.50 to 0.63) compared to chemotherapy alone. The combination may result in little to no difference in QoL (MD 0.8, 95% CI -2.11 to 3.71; 1 study, 486 participants; low-certainty evidence), but it increases the rate of any adverse event (grade ≥ 3) slightly (RR 1.11, 1.07 to 1.16; 3 studies, 1538 participants; high-certainty evidence). Hypertension (grade ≥ 3) was more common in arms with bevacizumab (RR 5.82, 95% CI 3.84 to 8.83; 3 studies, 1538 participants).  TKIs with chemotherapy may result in little to no difference in OS (HR 0.86, 95% CI 0.67 to 1.11; 1 study, 282 participants; low-certainty evidence), likely increase PFS (HR 0.56, 95% CI 0.44 to 0.72; 1 study, 282 participants; moderate-certainty evidence), and may have little to no effect on QoL (MD 6.1, 95% CI -0.96 to 13.16; 1 study, 146 participants; low-certainty evidence). Hypertension (grade ≥ 3) was more common with TKIs (RR 3.32, 95% CI 1.21 to 9.10). Recurrent EOC (platinum-resistant) Bevacizumab with chemotherapy and continued as maintenance increases OS (HR 0.73, 95% CI 0.61 to 0.88; 5 studies, 778 participants; high-certainty evidence) and likely results in a large increase in PFS (HR 0.49, 95% CI 0.42 to 0.58; 5 studies, 778 participants; moderate-certainty evidence). The combination may result in a large increase in hypertension (grade ≥ 2) (RR 3.11, 95% CI 1.83 to 5.27; 2 studies, 436 participants; low-certainty evidence). The rate of bowel fistula/perforation (grade ≥ 2) may be slightly higher with bevacizumab (RR 6.89, 95% CI 0.86 to 55.09; 2 studies, 436 participants). Evidence from eight studies suggest TKIs with chemotherapy likely result in little to no difference in OS (HR 0.85, 95% CI 0.68 to 1.08; 940 participants; moderate-certainty evidence), with low-certainty evidence that it may increase PFS (HR 0.70, 95% CI 0.55 to 0.89; 940 participants), and may result in little to no meaningful difference in QoL (MD ranged from -0.19 at 6 weeks to -3.40 at 4 months). The combination increases any adverse event (grade ≥ 3) slightly (RR 1.23, 95% CI 1.02 to 1.49; 3 studies, 402 participants; high-certainty evidence). The effect on bowel fistula/perforation rates is uncertain (RR 2.74, 95% CI 0.77 to 9.75; 5 studies, 557 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

Bevacizumab likely improves both OS and PFS in platinum-resistant relapsed EOC. In platinum-sensitive relapsed disease, bevacizumab and TKIs probably improve PFS, but may or may not improve OS. The results for TKIs in platinum-resistant relapsed EOC are similar. The effects on OS or PFS in newly-diagnosed EOC are less certain, with a decrease in QoL and increase in adverse events. Overall adverse events and QoL data were more variably reported than were PFS data. There appears to be a role for anti-angiogenesis treatment, but given the additional treatment burden and economic costs of maintenance treatments, benefits and risks of anti-angiogenesis treatments should be carefully considered.

Ovarian Cancer—Insights into Platinum Resistance and Overcoming It

Ovarian cancer is the most lethal gynecologic malignancy. Platinum-based chemotherapy is the backbone of treatment for ovarian cancer, and although the majority of patients initially have a platinum-sensitive disease, through multiple recurrences, they will acquire resistance. Platinum-resistant recurrent ovarian cancer has a poor prognosis and few treatment options with limited efficacy. Resistance to platinum compounds is a complex process involving multiple mechanisms pertaining not only to the tumoral cell but also to the tumoral microenvironment. In this review, we discuss the molecular mechanism involved in ovarian cancer cells’ resistance to platinum-based chemotherapy, focusing on the alteration of drug influx and efflux pathways, DNA repair, the dysregulation of epigenetic modulation, and the involvement of the tumoral microenvironment in the acquisition of the platinum-resistant phenotype. Furthermore, we review promising alternative treatment approaches that may improve these patients’ poor prognosis, discussing current strategies, novel combinations, and therapeutic agents.