Energy metabolism is the foundation of survival for all organisms, and mitochondria are the most important energy-supplying organelles in eukaryotic cells. However, the mitochondrial and energy/metabolism-related properties of cancer stem cells (CSCs), the stem cell-like subpopulation in tumor masses, remain unknown. In our study, we compared the masses of mitochondria and mitochondrial DNA (mtDNA), the mitochondrial membrane potential (Dwm), oxygen/glucose consumption, and the concentration of reactive oxygen species (ROS) and ATP between lung CSCs (LCSCs) and non-LCSCs. In addition, the change in features during differentiation was examined. Some mitochondrial and energy metabolism-related properties, such as perinuclear mitochondrial distribution, a lower quantity of mtDNA, higher Dwm, lower oxygen/glucose consumption, and lower intracellular concentrations of ROS and ATP, can be used as indicators of LCSCs.Increasing evidence indicates that cancer stem cells (CSCs) are initiators of the occurrence, development and recurrence of malignant tumors. 1 Thus, it is important to understand the biological characteristics of this subpopulation in the tumor mass. Due to the great efforts of many researchers, more and more specific features of CSCs have been revealed, such as cytotoxic resistance, invasiveness, proliferation/division, immunogenicity, hypoxic tolerance and the capacity of neovessels induction. 1,2 These findings aid in understanding the underlying mechanisms of growth, recurrence after therapy, immune escape and invasion/metastasis of malignant tumors.Energy metabolism is the foundation of survival for all organisms. As for mitochondria are the most important organelles that provide energy for sustaining the metabolic needs of eukaryotic cells. They are also known, vital components in many cell processes, including differentiation and apoptosis. 3 In recent years, mitochondrial and energy/metabolism-related features of normal adult/embryonic stem (ES) cells have been studied by an increasing number of researchers. 3,4 It has been suggested that the function and integrity of mitochondria may influence the viability, the proliferative and differentiation potential and the lifespan of normal stem cells. 3,5 Some features, including perinuclear mitochondrial arrangement, low ATP content, high rate of oxygen consumption, and low quantity of mitochondrial DNA (mtDNA), have been thought to be indicators of ''stemness'' of these undifferentiated cells. A departure from this profile suggests that cells are differentiating or perhaps becoming senescent. [3][4][5][6] In addition, it has been observed that much lower levels of reactive oxygen species (ROS), which are thought to be the by-products of mitochondrial biogenesis, are required for adult haemopoietic stem cells (HSCs) to remain quiescent and retain their stem features, such as self-renewal potential and multipotency. 7 At the same time, mitochondrialrelated abnormalities have also been considered to have an important role in the origin and development of ...

Lung cancer is the leading cause of cancer‐related death worldwide. In China, the incidence of lung cancer has grown rapidly, resulting in a large social and economic burden. Several researchers have devoted their studies to lung cancer and have demonstrated that there are many risk factors for lung cancer in China, including tobacco use, environmental pollution, food, genetics, and chronic obstructive pulmonary disease. However, the lung cancer incidence is still growing rapidly in China, and there is an even higher incidence among the younger generation. One explanation may be the triple‐neglect situation, in which medical policies that neglect prevention, diagnosis, and supportive care have increased patients' mortality and reduced their quality of life. Therefore, it is necessary to enhance the efficiency of prevention and early diagnosis not only by focusing more attention on treatment but also by drawing more attention to supportive care for patients with lung cancer. Cancer 2015;121:3080‐8. © 2015 American Cancer Society.

Cisplatin [cis-diaminodichloroplatinum (II) (CDDP)] is one of the most widely used and effective therapeutic agents for many kinds of cancers. However, its efficiency is limited due to development of drug resistance. In this study, we showed that CDDP resistance was associated with AKT1 overexpression and gene amplification in human lung cancer cells that acquired the drug resistance. We showed that AKT1 forced expression in the cells was sufficient to render the cells CDDP resistant, and that AKT1 inhibition by its dominant negative mutant reversed the CDDP-resistant cells to be CDDP sensitive. These results show that AKT1 activity is essential for regulating CDDP resistance in cultured lung cancer cells. To study whether these results were correlated with human lung cancer tumors, we randomly selected tumor samples from human lung cancer patients to study the correlation of AKT activation and CDDP resistance in clinical tumor samples. We showed that AKT activation was highly related to CDDP chemosensitivity in human tumor tissues. Our results further showed that AKT1 induced lung cancer cells to become resistant to CDDP through the mammalian target of the rapamycin (mTOR) signaling pathway. These studies conclude that AKT amplification and the mTOR pathway play an important role in human lung cancer cells acquiring CDDP resistance, which represents a new mechanism for acquiring CDDP resistance and a potential novel therapeutic target for overcoming CDDP resistance in human cancer in the future. [Cancer Res 2007;67(13):6325-32]

The distinction between mild pathogenic mtDNA mutations and population polymorphisms can be ambiguous because both are homoplasmic, alter conserved functions, and correlate with disease. One possible explanation for this ambiguity is that the same variant may have different consequences in different contexts. The NADH dehydrogenase subunit 1 (ND1) nucleotide 3394 T > C (Y30H) variant is such a case. This variant has been associated with Leber hereditary optic neuropathy and it reduces complex I activity and cellular respiration between 7% and 28% on the Asian B4c and F1 haplogroup backgrounds. However, complex I activity between B4c and F1 mtDNAs, which harbor the common 3394T allele, can also differ by 30%. In Asia, the 3394C variant is most commonly associated with the M9 haplogroup, which is rare at low elevations but increases in frequency with elevation to an average of 25% of the Tibetan mtDNAs (odds ratio = 23.7). In high-altitude Tibetan and Indian populations, the 3394C variant occurs on five different macrohaplogroup M haplogroup backgrounds and is enriched on the M9 background in Tibet and the C4a4 background on the Indian Deccan Plateau (odds ratio = 21.9). When present on the M9 background, the 3394C variant is associated with a complex I activity that is equal to or higher than that of the 3394T variant on the B4c and F1 backgrounds. Hence, the 3394C variant can either be deleterious or beneficial depending on its haplogroup and environmental context. Thus, this mtDNA variant fulfills the criteria for a common variant that predisposes to a "complex" disease.

Taken together, Angptl4 modulates vascular permeability, angiogenesis, inflammatory signaling, and associated diseases. The use of Angptl4-modulating agents such as certain drugs, food constituents (such as fatty acids), nuclear factor (such as PPARα), and bacteria may treat associated diseases such as tumor metastasis, ischemic-reperfusion injury, inflammation, and chronic low-grade inflammation. However, the diverse physiological functions of Angptl4 in different tissues can lead to potentially deleterious side effects when used as a therapeutic target. In this regard, a better understanding of the underlying mechanisms for Angptl4 in different tissues is necessary.