An Open-Label Randomized Controlled Trial Comparing the Efficacy and Safety of Pemetrexed-Carboplatin versus (Weekly) Paclitaxel-Carboplatin as First-Line Chemotherapy in Advanced Non-Squamous Non-Small Cell Lung Cancer

The double face of licorice-kansui herb pair: Cure or curse, depending on the combining ratio and mediated by hydrogen sulfide

BACKGROUND

The safety and efficacy of herbal medicines including traditional Chinese medicine (TCM) has been one of the major scientific problems in the medical field. In TCM prescriptions, reasonable herbal combinations bring stronger efficacy and low risk of toxicity. However, the rules and mechanisms for herbal combinations are far from complete understood yet.

PURPOSE

In this study, we investigated the efficacy-toxicity transformation of the licorice-kansui herbal combination under clinical equivalent doses, and study the inside mechanisms.

STUDY DESIGN

Licorice-kansui or glycyrrhetinic acid-kansuinine A combinations of different combining ratio were given to malignant pleural effusion mice as well as the IEC-6 and S-180 cells.

METHODS

The therapeutic and toxic effects were characterized by various indicators; the chemical changes were analyzed by LC-MS method; the role of H2S was also studied through its inhibitors.

RESULTS

Low-proportion of licorice combined with kansui exerted comparable therapeutic effects to cisplatin, by reducing pleural effusion, promoting respiration, increasing urine volume, protecting lung tissue, and inhibiting tumor cells by inducing oxidative stress and apoptosis. On the other hand, high-proportion of licorice combined with kansui had poor therapeutic effect but induced oxidative stress, inflammation and tissue damages, especially to the small intestine. This efficacy-toxicity transformation was also reproduced by the glycyrrhetinic acid-kansuinine A combination on IEC-6 epithelial cells and S-180 tumor cells. The transformation was not simply caused by the in-solution solubilization effects of licorice during co-decocted with kansui. Furthermore, the therapeutic and toxic effects were both highly related to the hydrogen sulfide level and its anabolic enzymes, cystathionine-gamma-lyase (CSE) or cystathionine beta-synthase (CBS), either in tissues or in-vitro cells. By inhibiting CSE or CBS, all the therapeutic or toxic effects were abolished both in-vivo and in-vitro. Moreover, the intestinal sulfide-reducing bacteria Desulfovibrio and body drug-metabolism were also important variants influencing the efficacy-toxicity transformation of licorice-kansui herbal combination.

CONCLUSION

This study comprehensively uncovered the rules of licorice-kansui herbal combination, and for the first time confirmed that H2S plays a crucial role in mediating its efficacy-toxicity transformation. Our study not only supports the reasonable clinical usage of these two herbs but also provide ideas and methods for the study of other herb pairs in TCM prescriptions.

TRIM17-mediated ubiquitination and degradation of RBM38 promotes cisplatin resistance in non-small cell lung cancer

Cisplatin (CDDP)-based chemotherapy is commonly used to treat advanced non-small cell lung cancer (NSCLC). However, the efficacy is limited by the development of drug resistance. Tripartite motif (TRIM) proteins typically have E3 ubiquitin ligase activities and modulate protein stability. In the present study, we screened for chemosensitivity-regulating TRIM proteins using CDDP-resistant NSCLC cell lines. We show that TRIM17 is upregulated in CDDP-resistant NSCLC cells and tumors compared to CDDP-sensitive counterparts. NSCLC patients with high TRIM17 expression in tumors have shorter progression-free survival than those with low TRIM17 expression after CDDP chemotherapy. Knockdown of TRIM17 increases the sensitivity of NSCLC cells to CDDP both in vitro and in vivo. In contrast, overexpression of TRIM17 promotes CDDP resistance in NSCLC cells. TRIM17-mediated CDDP resistance is associated with attenuation of reactive oxygen species (ROS) production and DNA damage. Mechanistically, TRIM17 interacts with RBM38 and promotes K48-linked ubiquitination and degradation of RBM38. TRIM17-induced CDDP resistance is remarkably reversed by RBM38. Additionally, RBM38 enhances CDDP-induced production of ROS. In conclusion, TRIM17 upregulation drives CDDP resistance in NSCLC largely by promoting RBM38 ubiquitination and degradation. Targeting TRIM17 may represent a promising strategy for improving CDDP-based chemotherapy in NSCLC.

A phase II study of metformin plus pemetrexed and carboplatin in patients with non-squamous non-small cell lung cancer (METALUNG)

Immune checkpoint inhibitors (ICIs) ± chemotherapy is the standard treatment for driver mutation-negative non-small cell lung cancer (NSCLC). However, accessibility to ICIs in LMICs is limited due to high cost, and platinum-based chemotherapy remains the mainstay of treatment. Metformin has anticancer properties, and studies suggest synergism between metformin and pemetrexed. Based on preclinical evidence, this combination may be more beneficial for STK11-mutated NSCLC, a subgroup, inherently resistant to ICIs. In this Simon two-stage, single-arm phase 2 trial, we investigated metformin with pemetrexed-carboplatin (PC) in patients with treatment-naive stage IV non-squamous NSCLC. The primary outcome was 6-month progression-free survival (PFS) rate. Secondary outcomes were safety, overall survival (OS), overall response rate (ORR), proportion of STK11 mutation, and effect of STK11 mutation on 6-month PFS rate. The study was terminated for futility after interim analysis. The median follow-up was 34.1 months. The 6-month PFS rate was 28% (95% CI 12.4-0.46). The median PFS and OS were 4.5 (95% CI 2.2-6.1) and 7.4 months (95% CI 5.3-15.3), respectively. The ORR was 72%. Gastrointestinal toxicities were the most common. No grade 4/5 toxicities were reported. Targeted sequencing was possible in nine cases. Two patients had STK11 mutation and a poor outcome (PFS < 12 weeks). We could not demonstrate the benefit of metformin with CP in terms of improvement in 6-month PFS rate; however, the combination was safe (CTRI/2019/02/017815).