Activation of the pentose phosphate pathway in macrophages is crucial for granuloma formation in sarcoidosis

肉芽腫形成に特異的な代謝経路の発見 --ペントースリン酸回路の制御による新規治療--. 京都大学プレスリリース. 2023-12-01.More than skin-deep: Kyoto researchers discover metabolic pathway specific to granuloma formation in patients. 京都大学プレスリリース. 2023-12-07.Sarcoidosis is a disease of unknown etiology in which granulomas form throughout the body and is typically treated with glucocorticoids, but there are no approved steroid-sparing alternatives. Here, we investigated the mechanism of granuloma formation using single-cell RNA-Seq in sarcoidosis patients. We observed that the percentages of triggering receptor expressed on myeloid cells 2–positive (TREM2-positive) macrophages expressing angiotensin-converting enzyme (ACE) and lysozyme, diagnostic makers of sarcoidosis, were increased in cutaneous sarcoidosis granulomas. Macrophages in the sarcoidosis lesion were hypermetabolic, especially in the pentose phosphate pathway (PPP). Expression of the PPP enzymes, such as fructose-1, 6-bisphosphatase 1 (FBP1), was elevated in both systemic granuloma lesions and serum of sarcoidosis patients. Granuloma formation was attenuated by the PPP inhibitors in in vitro giant cell and in vivo murine granuloma models. These results suggest that the PPP may be a promising target for developing therapeutics for sarcoidosis

Runx2 is required for the proliferation of osteoblast progenitors and induces proliferation by regulating Fgfr2 and Fgfr3

Runx2 and Sp7 are essential transcription factors for osteoblast differentiation. However, the molecular mechanisms responsible for the proliferation of osteoblast progenitors remain unclear. The early onset of Runx2 expression caused limb defects through the Fgfr1?3 regulation by Runx2. To investigate the physiological role of Runx2 in the regulation of Fgfr1?3, we compared osteoblast progenitors in Sp7?/? and Runx2?/? mice. Osteoblast progenitors accumulated and actively proliferated in calvariae and mandibles of Sp7?/? but not of Runx2?/? mice, and the number of osteoblast progenitors and their proliferation were dependent on the gene dosage of Runx2 in Sp7?/? background. The expression of Fgfr2 and Fgfr3, which were responsible for the proliferation of osteoblast progenitors, was severely reduced in Runx2?/? but not in Sp7?/? calvariae. Runx2 directly regulated Fgfr2 and Fgfr3, increased the proliferation of osteoblast progenitors, and augmented the FGF2-induced proliferation. The proliferation of Sp7?/? osteoblast progenitors was enhanced and strongly augmented by FGF2, and Runx2 knockdown reduced the FGF2-induced proliferation. Fgfr inhibitor AZD4547 abrogated all of the enhanced proliferation. These results indicate that Runx2 is required for the proliferation of osteoblast progenitors and induces proliferation, at least partly, by regulating Fgfr2 and Fgfr3 expression

Prognostic impact of clinical factors for immune checkpoint inhibitor with or without chemotherapy in older patients with non-small cell lung cancer and PD-L1 TPS ≥ 50%

IntroductionThe proportion of older patients diagnosed with advanced-stage non-small cell lung cancer (NSCLC) has been increasing. Immune checkpoint inhibitor (ICI) monotherapy (MONO) and combination therapy of ICI and chemotherapy (COMBO) are standard treatments for patients with NSCLC and programmed cell death ligand-1 (PD-L1) tumor proportion scores (TPS) ≥ 50%. However, evidence from the clinical trials specifically for older patients is limited. Thus, it is unclear which older patients benefit more from COMBO than MONO.MethodsWe retrospectively analyzed 199 older NSCLC patients of Eastern Cooperative Oncology Group performance status (ECOG PS) 0-1 and PD-L1 TPS ≥ 50% who were treated with MONO or COMBO. We analyzed the association between treatment outcomes and baseline patient characteristics in each group, using propensity score matching.ResultsOf the 199 patients, 131 received MONO, and 68 received COMBO. The median overall survival (OS; MONO: 25.2 vs. COMBO: 42.2 months, P = 0.116) and median progression-free survival (PFS; 10.9 vs. 11.8 months, P = 0.231) did not significantly differ between MONO and COMBO group. In the MONO group, OS was significantly shorter in patients without smoking history compared to those with smoking history [HR for smoking history against non-smoking history: 0.36 (95% CI: 0.16-0.78), P = 0.010]. In the COMBO group, OS was significantly shorter in patients with PS 1 than those with PS 0 [HR for PS 0 against PS 1: 3.84 (95% CI: 1.44-10.20), P = 0.007] and for patients with squamous cell carcinoma (SQ) compared to non-squamous cell carcinoma (non-SQ) [HR for SQ against non-SQ: 0.17 (95% CI: 0.06-0.44), P < 0.001]. For patients with ECOG PS 0 (OS: 26.1 months vs. not reached, P = 0.0031, PFS: 6.5 vs. 21.7 months, P = 0.0436) or non-SQ (OS: 23.8 months vs. not reached, P = 0.0038, PFS: 10.9 vs. 17.3 months, P = 0.0383), PFS and OS were significantly longer in the COMBO group.ConclusionsECOG PS and histological type should be considered when choosing MONO or COMBO treatment in older patients with NSCLC and PD-L1 TPS ≥ 50%