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We present chemical abundance ratios of 70 star-forming galaxies at$z\sim4$-10 observed by the JWST/NIRSpec ERO, GLASS, and CEERS programs. Amongthe 70 galaxies, we have pinpointed 2 galaxies, CEERS_01019 at $z=8.68$ andGLASS_150008 at $z=6.23$, with extremely low C/N ([C/N]$\lesssim -1$),evidenced with CIII]$\lambda\lambda$1907,1909, NIII]$\lambda$1750, andNIV]$\lambda\lambda$1483,1486, which show high N/O ratios ([N/O]$\gtrsim 0.5$)comparable with the one of GN-z11 regardless of whether stellar or AGNradiation is assumed. Such low C/N and high N/O ratios found in CEERS_01019 andGLASS_150008 (additionally identified in GN-z11) are largely biased towards theequilibrium of the CNO cycle, suggesting that these 3 galaxies are enriched bymetals processed by the CNO cycle. On the C/N vs. O/H plane, these 3 galaxiesdo not coincide with Galactic HII regions, normal star-forming galaxies, andnitrogen-loud quasars with asymptotic giant branch stars, but globular-cluster(GC) stars, indicating a connection with GC formation. We compare C/O and N/Oof these 3 galaxies with those of theoretical models, and find that these 3galaxies are explained by scenarios with dominant CNO-cycle materials, i.e.Wolf-Rayet stars, supermassive ($10^{3}-10^{5}\ M_{\odot}$) stars, and tidaldisruption events, interestingly with a requirement of frequent directcollapses. For all the 70 galaxies, we present measurements of Ne/O, S/O, andAr/O, together with C/O and N/O. We identify 4 galaxies with very low Ne/O,$\log(\rm Ne/O)<-1.0$, indicating abundant massive ($\gtrsim30\ M_\odot$)stars.

JWST Identification of Extremely Low C/N Galaxies with [N/O]$\gtrsim  0.5$ at $z\sim 6-10$ Evidencing the Early CNO-Cycle Enrichment and a  Connection with Globular Cluster Formation