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Lung cancer is the leading cause of cancer-related death worldwide. Non-small cell lung cancer (NSCLC) accounts for 80% of lung cancer cases and the reported overall 5-year survival rate is less than 5%. Natural medicines have attracted much attention due to their lower toxicity and fewer side effects. Trichosanthes kirilowii Maxim (TKM) fruits are commonly used in cancer treatment in combination with other Chinese medicinal herbs. However, little is known about their biological functions and mechanisms in NSCLC cells. In this study, we investigated the efficacy of TKM fruits in NSCLC cells using cell proliferation, invasion, migration, and anchorage independent assays and a Xenograft NSCLC tumor model, and explored the possible biological mechanism by flow cytometric analysis, cDNA microarray and real-time PCR. Results showed that TKM fruits significantly suppressed NSCLC cell proliferation, migration, invasion, tumorigenicity and tumor growth, and significantly extended the survival time of NSCLC-bearing mice. Flow cytometric analysis showed that TKM fruits significantly induced G2-M arrest, necrosis and apoptosis in NSCLC cells. cDNA microarray analysis revealed that TKM fruits regulated the differential expression of 544 genes, and the differential expression of selected genes was also confirmed. Gene ontology (GO) analysis showed that 18 of first 20 biological processes were involved in cell cycle and mitosis. These results indicate that TKM fruits have certain inhibitory effect on NSCLC cells through cell-cycle and mitosis arrest, and suggest that TKM fruits may be an important resource for developing new antitumor drugs, and a potent natural product for treating patients with NSCLC.

We propose a reaction-diffusion model of the mechanisms involved in the healing of corneal surface wounds. The model focuses on the stimulus for increased mitotic and migratory activity, specifically the role of epidermal growth factor. We determine an analytic approximation for the speed of travelling wave solutions of the model in terms of the parameters and verify the results numerically. By comparing the predicted speed with experimentally measured healing rates, we conclude that serum-derived factors can alone account for the overall features of the healing process, but that the supply of growth factors by the tear film, in the absence of serum-derived factors, is not sufficient to give the observed healing rate. Numerical solutions of the model equations also confirm the importance of both migration and mitosis for effective wound healing. By modifying the model, we obtain an analytic prediction for the healing rate of corneal surface wounds when epidermal growth factor is applied topically to the wound.

A hydrate model for the DNA–H₂O system is proposed. For the notions developed, available data on a tendency of H₂O molecules to form structured hydrates containing atomic groups, molecules, or atoms housed within the structural cavities formed by H-bonded H₂O molecules are used. It is shown that the large and small cavities of the hydrate structure II are in close geometric agreement with N-bases and deoxyribose and with other atomic groups of DNA molecules, respectively. On the basis of the model proposed and with the Watson–Crick base-pairing scheme, the number of pairs of N-bases per helix turn (11.25), the density (1.161 g/cm³), and the helix step (0.567 nm) for the quasi-equilibrium DNA (RNA)–water system are computed, the last value nearly coinciding with the well-known alpha-helix step in the protein secondary structure (5.44 nm). Assumptions on the phenomenology of some stages of mitosis are presented.

Programmed cell death, or apoptosis, and controlled cell division, or mitosis, are two highly regulated processes in the cell cycle. A balance between apoptosis and mitosis is critical for multiple distinct states including embryonic development, immune cell activation, stem cell differentiation, tissue formation (wound healing), and tumor prevention, among others. A cell undergoing apoptosis shows a series of characteristic morphological changes similar to normal mitosis and an aberrant form of mitosis. During each of these processes, nuclear chromatin condenses, the nuclear lamina and cytoplasmic membranes disintegrate, and cells decrease in volume. The morphological resemblance among cells undergoing these processes suggests that the underlying intracellular signaling pathways influence the mitotic cell fate. In this paper, the relationship of intracellular signaling pathways, cell cycle dynamics, and apoptotic cell signaling pathways is discussed. The mitogen-activated protein kinases/extracellular signal-regulated kinases (MAPK/Ras/Raf/ERK), phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt), Janus kinase/signal transducer and activator of transcription (JAK/STAT), wingless-related integration site (Wnt), and transforming growth factor beta (TGF-$\beta )$ are major cell signaling pathways that transmit signals from multiple cell surface receptors to transcription factors in the nucleus. The pathways are stimulated by cytokines, growth factors, and external stimuli, i.e., reactive oxygen species which induce signal transduction pathways and regulate complex processes such as cell cycle progression, cell proliferation, cellular growth, differentiation, and apoptosis. Aberrant mutations in particular genes and proteins of these pathways contribute to cancers usually by inhibiting pro-apoptotic proteins (e.g., Bak, Bax, Noxa, Puma, etc.) and stimulating antiapoptotic proteins (e.g., Bcl-2, Bcl-XL, Mcl-1, etc.). The cell cycle is regulated by intracellular signaling pathways such as the MAPK/Ras/Raf/ERK and PI3K pathways to produce the synthesis of cyclin D and other mitosis regulating proteins (Myc and Jun). Cyclin D1 binds to cyclin-dependent kinase (CDK) 4 and CDK 6 (CDK4/6) to form an effective complex, activate several substrates, and initiate the cell cycle. The prominent molecules that regulate signaling pathways in normal and cancer cells are described.

As breast cancer is a substantial threat to the lives of women, it has become a major health issue in the world over the past 50 years, and its incidence has increased in the recent years. Early diagnosis and suitable treatment is relatively important. In the process of breast screening, tissue biopsy is an important operation in determining the presence of breast cancer. It not only provides an accurate diagnosis of the disease but also determines the prognosis for breast cancer. The main goal of this study is to develop a breast cancer diagnosis system based on histopathology and a sequence of image-processing technologies to analyze H&E stained images of breast tissues. The proposed system can automatically detect the mitosis of nuclei and analyze the size and the shape of nuclei to evaluate the duct structure of the breast tissue. Moreover, it provides physicians quantitative prognosis and classification of tissue malignancy, which will improve the diagnostic accuracy and efficiency of the cancer.

Successful culture of the obligatorily anaerobic symbionts residing in the hindgut of the wood-eating cockroach Cryptocercus punctulatus now permits continuous observation of mitosis in individual Barbulanympha cells. In Part I of this two-part paper, we report methods for culture of the protozoa, preparation of microscope slide cultures in which Barbulanympha survived and divided for up to 3 days, and an optical arrangement which permits observation and through-focus photographic recording of dividing cells, sequentially in differential interference contrast and rectified polarized light microscopy. We describe the following prophase events and structures: development of the astral rays and large extranuclear central spindle from the tips of the elongate-centrioles; the fine structure of spindle fibers and astral rays which were deduced in vivo from polarized light microscopy and seen as a particular array of microtubules in thin-section electron micrographs; formation of chromosomal spindle fibers by dynamic engagement of astral rays to the kinetochores embedded in the persistent nuclear envelope; and repetitive shortening of chromosomal spindle fibers which appear to hoist the nucleus to the spindle surface, cyclically jostle the kinetochores within the nuclear envelope, and churn the prophase chromosomes. The observations described here and in Part II have implications both for the evolution of mitosis and for understanding the mitotic process generally.

The rationale, design and general performance of the CPM (centrifuge polarizing microscope) were described in Part I of this study (Inoué et al. J. Microsc.201 (2001) 341–356. In this second part, we describe observations on several biological samples that we have explored over the past two years using the CPM.

As described in the first part of the study, although the CPM was basically designed as a high-extinction centrifuge polarizing microscope, it also allows observations of the specimen exposed to high centrifugal fields up to 10 500 × g (earth's gravitational acceleration) in fluorescence (532-nm excitation) and in DIG (differential interference or Nomarski contrast).

In this paper, a scheme for mitosis detection in breast cancer histological images is proposed. The whole scheme includes three main stages, images pre-processing stage, feature extraction stage and classification stage. In the candidate detection phase, morphological operation and marker-controlled watershed segmentation algorithm to generate candidates are performed. In the feature extraction stage, a total of 90 features including conventional morphological features and circular Gabor features of the candidate region is extracted and circular Gabor filter banks are designed for feature extraction. In classification stage, three different AdaBoost algorithms are employed to classify the candidates, the results shows that Modest AdaBoost achieves highest accuracy of 73.2%.