Sucrose transporters (SUCs or SUTs) play a central role, as they orchestrate sucrose allocation both intracellularly and at the whole plant level. Previously, we found AtSUC4 mutants changing sucrose distribution under drought and salt stresses. Here, we systematically examined the role of Arabidopsis AtSUC2 and AtSUC4 in response to abiotic stress. The results showed significant induction of AtSUC2 and AtSUC4 in salt, osmotic, low temperature and exogenous abscisic acid (ABA) treatments by public microarray data and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) analyses. The loss-of-function mutation of AtSUC2 and AtSUC4 led to hypersensitive responses to abiotic stress and ABA treatment in seed germination and seedling growth. These mutants also showed higher sucrose content in shoots and lower sucrose content in roots, as compared with that in wild-type plants, and inhibited the ABA-induced expression of many stress- and ABA-responsive genes, especially ABFs and ABF-downstream and upstream genes. The loss-of-function mutant of AtSUC3, a unique putative sucrose sensor, reduced the expression of AtSUC2 and AtSUC4 in response to abiotic stresses and ABA. These findings confirmed that AtSUC2 and AtSUC4 are important regulators in plant abiotic stress tolerance that use an ABA signaling pathway, which may be crossed with sucrose signaling.

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Our study showed that quantitative radiomic imaging features of breast tumor extracted from digital mammograms are associated with breast cancer subtypes. Future larger studies are needed to further evaluate the findings.

Circulating tumor cells (CTCs), which have stem cell-like characteristics, might play a crucial role in cancer metastasis. CD44 has been identified as gastric cancer (GC) stem cell (CSC) marker. Here, the prognostic significance of CD44-positive CTCs in GC patients was investigated. CTCs were detected in 27 of 45 GC patients. The presence of CTCs was significantly associated with lymph node metastasis, distant metastasis, and recurrence (P = 0.007, P = 0.035, and P = 0.035, resp.). Nineteen of the 27 CTC-positive patients had CD44-positive CTCs. These patients were more likely to develop metastasis and recurrence than patients with CD44-negative CTCs. CD44-positive CTC counts were higher in recurrent patients than in the nonrecurrent ones (means 4.8 and 1.9, resp.; P = 0.010). Furthermore, 13 of 19 patients with CD44-positive CTCs developed recurrent disease, and the mean time to recurrence was shorter than that in patients with CD44-negative CTCs (10.54 ± 5.55 and 19.13 ± 9.72 months, resp.; P = 0.04). COX proportional hazards model indicated that the presence of CD44-positive CTCs and TNM stage were independent predictors of recurrence for GC (P = 0.030 and 0.008). So identifying the stem cell-like CTC subset may provide more clinically useful prognostic information than only detecting CTCs.