Elucidation and Regulation of Tyrosine Kinase Inhibitor Resistance in Renal Cell Carcinoma Cells from the Perspective of Glutamine Metabolism

Evaluation of efficacy and safety of targeted therapy and immune checkpoint inhibitors in metastatic colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is among the most prevalent and deadly cancers globally, particularly in China. Treatment challenges remain in advanced and metastatic cases, especially in third- and fourth-line settings. The combination of targeted therapies with immune checkpoint inhibitors (ICIs) has shown potential in addressing the limitations of single-agent treatments.

AIM

To evaluate the efficacy and safety of targeted therapy (TT) alone and in combination with ICIs for metastatic CRC (mCRC).

METHODS

A multicenter retrospective observational study was conducted to evaluate the efficacy and safety of TT alone and in combination with ICIs for mCRC. A total of 99 patients treated with regorafenib or fruquintinib, with or without ICIs, were enrolled. Propensity score matching (PSM) and inverse probability weighting (IPW) were employed to balance baseline characteristics. The primary endpoint was progression-free survival (PFS), while overall survival (OS) and safety were secondary.

RESULTS

Patients who received combined therapy showed significantly longer median PFS rates compared to those who underwent TT in all analyses (original: 6.0 vs 3.4 months, P < 0.01; PSM: 6.15 vs 4.25 months, P < 0.05; IPW: 5.6 vs 3.3 months, P < 0.01). Although the median OS showed a trend toward improvement in the combination group, the difference was insignificant. Cox regression analysis revealed that combining TT with ICIs significantly reduced the risk of disease progression (hazard ratio = 0.38, P < 0.001). Adverse events (AEs) were generally manageable with both regimens, while serious AEs (grade 3-4) were primarily hypertension, fatigue, and reduced platelet counts. All AEs were controlled effectively by symptomatic treatment or discontinuation of the drug, and no treatment-related deaths were observed.

CONCLUSION

The combination of TT with ICIs offers a significant advantage in terms of PFS for patients with advanced mCRC, accompanied by a favorable safety profile. These findings underscore the benefits of combination therapy in this setting, warranting further investigation in larger prospective clinical trials.

Association between folate and glutamine metabolism and prognosis of kidney cancer

Background

Recent studies have shown that folate metabolism might influence cancer progression by regulating mitochondrial metabolism and glutamine is involved in the development and progression of several malignancies. This study aimed to explore the association between folate and glutamine metabolism and prognosis of kidney cancer.

Methods

We performed expression analysis, survival analysis, genetic alteration analysis, and tumor immune infiltrate analysis of related genes using platforms such as UALCAN, GEPIA, GEPIA2, cBioPortal, and TIMER. Serum folate, vitamin B12, and methylmalonic acid levels and clinical information of participants in the United States diagnosed with kidney cancer was obtained from the National Health and Nutrition Examination Survey (NHANES) and analyzed using software R.

Results

We observed that RNA expression levels of certain folate and glutamine metabolism-related genes, particularly MTHFD2 and SLC1A5, were associated with the prognosis of kidney renal clear cell carcinoma (KIRC). Expression differences in these genes were notable between high-stage and low-stage and N1 vs. N0 lymph node metastasis status in KIRC. There was a positive association between glutamine metabolism-related genes and folate metabolism-related genes in KIRC. SLC1A5 was positively correlated with MTHFD2 in KIRC. Folate and glutamine metabolism might play a synchronous role in KIRC prognosis. Strong correlations between MTHFD2 and SLC1A5 expression with KIRC immune infiltrates were found. Higher levels of serum folate may be related to improved cancer-specific survival (CSS) in kidney cancer patients in the U.S.

Conclusion

Folate and glutamine metabolism-related genes, especially SLC1A5 and MTHFD2, were associated with the prognosis, tumor stage, and lymph node metastasis status in KIRC. Higher KIRC SLC1A5 or MTHFD2 expression levels were associated with higher tumor stages, increased lymph node metastasis possibilities, poorer OS, and poorer RFS. Elevated levels of serum folate may be associated with improved CSS in kidney cancer patients in the United States.