Lorlatinib Induces Durable Disease Stabilization in a Pancreatic Cancer Patient with a ROS1 p.L1950F Mutation: Case Report

Current treatment and novel insights regarding ROS1-targeted therapy in malignant tumors

BACKGROUND

The proto-oncogene ROS1 encodes an intrinsic type I membrane protein of the tyrosine kinase/insulin receptor family. ROS1 facilitates the progression of various malignancies via self-mutations or rearrangements. Studies on ROS1-directed tyrosine kinase inhibitors have been conducted, and some have been approved by the FDA for clinical use. However, the adverse effects and mechanisms of resistance associated with ROS1 inhibitors remain unknown. In addition, next-generation ROS1 inhibitors, which have the advantage of treating central nervous system metastases and alleviating endogenous drug resistance, are still in the clinical trial stage.

METHOD

In this study, we searched relevant articles reporting the mechanism and clinical application of ROS1 in recent years; systematically reviewed the biological mechanisms, diagnostic methods, and research progress on ROS1 inhibitors; and provided perspectives for the future of ROS1-targeted therapy.

RESULTS

ROS1 is most expressed in malignant tumours. Only a few ROS1 kinase inhibitors are currently approved for use in NSCLC, the efficacy of other TKIs for NSCLC and other malignancies has not been ascertained. There is no effective standard treatment for adverse events or resistance to ROS1-targeted therapy. Next-generation TKIs appear capable of overcoming resistance and delaying central nervous system metastasis, but with a greater incidence of adverse effects.

CONCLUSIONS

Further research on next-generation TKIs regarding the localization of ROS1 and its fusion partners, binding sites for targeted drugs, and coadministration with other drugs is required. The correlation between TKIs and chemotherapy or immunotherapy in clinical practice requires further study.

Efficacy and safety of apatinib combined with radiotherapy in the treatment of advanced pancreatic cancer: a meta-analysis

OBJECTIVE

At present, pancreatic cancer (PC) has a high morbidity and mortality rate and a poor prognosis. The aim of this article was to study the efficacy and safety of apatinib combined with radiotherapy in the treatment of advanced PC.

METHODS

The PubMed, Cochrane Library, Embase, Wanfang, CNKI, VIP, and CBM databases were searched by computer to identify studies on the application of apatinib in patients with advanced PC. The patients in the included study were divided into an observation group (apatinib combined with radiotherapy) and a control group (radiotherapy only), and meta-analysis was performed for each outcome with Revman 5.4 software. This study was successfully registered on the PROSPERO website, and the registration number is CRD: 42,022,384,056 (available at https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=384056 ).

RESULTS

A total of 7 randomized controlled trials (RCTs) with 428 patients were included, including 215 in the observation group and 213 in the control group. Compared with the control group, the observation group showed a greater objective response rate [OR = 3.26, 95% CI (2.18, 4.87), P < 0.0001], disease control rate [OR = 5.04, 95% CI (3.12, 8.12), P < 0.0001], complete response rate [OR = 3.87, 95% CI (1.51, 9.88), P = 0.005], and partial response rate [OR = 2.43, 95% CI (1.63, 3.61), P < 0.001], The 1-year survival rate [OR = 2.39, 95% CI (1.15, 4.96), P < 0.05], 2-year survival rate [OR = 2.41, 95% CI (1.03, 5.61), P < 0.05], progression-free survival time [MD = 1.17, 95% CI (0.37, 1.96), P < 0.05], overall survival time [MD = 1.47, 95% CI (0.13, 2.80), P < 0.05], while the stability rate [OR = 1.14, 95% CI (0.72, 1.81), P = 0.58] and various complications were not significantly different between the two groups.

CONCLUSION

Apatinib combined with radiotherapy was more effective than radiotherapy alone in the treatment of advanced pancreatic cancer (PC), and apatinib had acceptable safety. However, since our study was limited by the quantity and quality of the included studies, we look forward to more large-sample, multicentre, and high-quality RCTs in the future to verify the conclusions.

Refining the Treatment of Pancreatic Cancer From Big Data to Improved Individual Survival

Pancreatic cancer is one of the most lethal cancers worldwide, most notably in Europe and North America. Great strides have been made in combining the most effective conventional therapies to improve survival at least in the short and medium term. The start of treatment can only be made once a diagnosis is made, which at this point, the tumor volume is already very high in the primary cancer and systemically. If caught at the earliest opportunity (in circa 20% patients) surgical resection of the primary followed by combination chemotherapy can achieve 5-year overall survival rates of 30%-50%. A delay in detection of even a few months after symptom onset will result in the tumor having only borderline resectabilty (in 20%-30% of patients), in which case the best survival is achieved by using short-course chemotherapy before tumor resection as well as adjuvant chemotherapy. Once metastases become visible (in 40%-60% of patients), cure is not possible, palliative cytotoxics only being able to prolong life by few months. Even in apparently successful therapy in resected and borderline resectable patients, the recurrence rate is very high. Considerable efforts to understand the nature of pancreatic cancer through large-scale genomics, transcriptomics, and digital profiling, combined with functional preclinical models, using genetically engineered mouse models and patient derived organoids, have identified the critical role of the tumor microenvironment in determining the nature of chemo- and immuno-resistance. This functional understanding has powered fresh and exciting approaches for the treatment of this cancer.

Comprehensive Molecular Landscape of Cetuximab Resistance in Head and Neck Cancer Cell Lines

Cetuximab is the sole anti-EGFR monoclonal antibody that is FDA approved to treat head and neck squamous cell carcinoma (HNSCC). However, no predictive biomarkers of cetuximab response are known for HNSCC. Herein, we address the molecular mechanisms underlying cetuximab resistance in an in vitro model. We established a cetuximab resistant model (FaDu), using increased cetuximab concentrations for more than eight months. The resistance and parental cells were evaluated for cell viability and functional assays. Protein expression was analyzed by Western blot and human cell surface panel by lyoplate. The mutational profile and copy number alterations (CNA) were analyzed using whole-exome sequencing (WES) and the NanoString platform. FaDu resistant clones exhibited at least two-fold higher IC50 compared to the parental cell line. WES showed relevant mutations in several cancer-related genes, and the comparative mRNA expression analysis showed 36 differentially expressed genes associated with EGFR tyrosine kinase inhibitors resistance, RAS, MAPK, and mTOR signaling. Importantly, we observed that overexpression of KRAS, RhoA, and CD44 was associated with cetuximab resistance. Protein analysis revealed EGFR phosphorylation inhibition and mTOR increase in resistant cells. Moreover, the resistant cell line demonstrated an aggressive phenotype with a significant increase in adhesion, the number of colonies, and migration rates. Overall, we identified several molecular alterations in the cetuximab resistant cell line that may constitute novel biomarkers of cetuximab response such as mTOR and RhoA overexpression. These findings indicate new strategies to overcome anti-EGFR resistance in HNSCC.